There are plenty reasons why.
https://commons.wikimedia.org/wiki/File:Legality_of_firearm_...
And not a single one was provided, curious!
It does not make your weapon more lethal, it does not make your weapon cheaper, it does not increase the capacity of your weapon. Sounds like more copium to me.
Wear ear muffs if you are worried about your hearing.
A sibling post writes "Firing a gun with no hearing protection is a pretty jarring experience", but let's be clear: ANY exposure to sound over 140 dB or so mean instantaneous permanent hearing loss. Period. "Jarring" isn't quite the adjective. A single use doesn't mean you just go deaf or even "merely" get tinnitus, but it does mean you just burned some of your hearing forever. It doesn't heal and there isn't any treatment. For practice with regular usage even with ear protection it's quite possible to exceed NIOSH limits on sound exposure. Obviously lots of people just live with that, but hearing loss is serious. There is environmental damage and bystanders to consider as well. All of this of course ignores that for self defense at home someone might not have time to put on ear pro at all.
The only way to really make guns hearing safe is to double up on multiple physically different methods combining both hearing protection and sound reduction of the gun itself. A suppressor can take a gun down to the 130-150dB range, and then a further 20-30 dB of ear protection takes that to 100-130dB for the shooter. Subsonic ammunition can also be use, sacrificing performance to eliminate the supersonic crack and somewhat reduce sound too.
Suppressors should just be standard safety equipment. The Hollywood meme where you screw something onto a rifle and now it sounds like a can of compressed air is as real as people jumping through plate glass windows (actually made of sugar) and other such ridiculous physics. 130dB is still LOUD, you will absolutely here that from a distance. The original impetus in America for trying to make them a thing only for rich people was concerns about "poaching" by poor people and ties into a bunch of class warfare there. It's an obsolete consideration for a host of reasons at this point. The societal benefits of less hearing damage would be considerable, it's now known quite a number of significant issues like dementia can be influenced by hearing loss.
Maybe it’s true! But if so, I am definitely surprised as heck, since I grew up around guns and gun safety. It was a big part of my upbringing. My gramps took me shooting underneath some bridge somewhere when I was like 11, and let me loose off a few rounds of a magnum. We just wore earplugs + earmuffs like usual. It felt like a hand cannon in the truest sense of the word, so it’s hard to imagine a louder handheld gun.
EDIT: Randomly searching for things like “is hearing protection always enough for guns?” doesn’t seem to bring up anything to support this, and all the links seem to say variations of “yes, hearing protection will always prevent hearing loss when shooting.” E.g. from ASHA: https://www.asha.org/public/hearing/recreational-firearm-noi...
> The good news is that people can prevent hearing loss by using appropriate hearing protective devices (HPDs), such as earmuffs or earplugs.
And ASHA’s credentials seem pretty impressive:
> The American Speech-Language-Hearing Association (ASHA) is the national professional, scientific, and credentialing association for 223,000 members and affiliates who are audiologists; speech-language pathologists; speech, language, and hearing scientists; audiology and speech-language pathology support personnel; and students.
So would you mind pointing me to anything that supports the idea that a suppressor is a necessary component to prevent hearing loss, and that hearing protection alone isn’t enough? I’d appreciate it, since it’s a chance to reshape my worldview. I’m always willing to suspend disbelief in the face of evidence.
Any ear protection is better then nothing and there is certainly more than one way to do it. But damage is cumulative, so it's worth considering what kind of exposure one is seeing. I think lots of people just accept it or don't even know, they "get used to it" which means they've lost high frequency hearing in particular but the ear protection is helping make sure they can still hear conversations and avoid tinnitus ok (or at least raise their odds). The law plus natural human impulse also perverts the situation, people want things they enjoy or think are important to also not have serious drawbacks, industry wants people to feel shooting is safe, and government (not just the law [0]) makes getting a suppressor a real pain in the butt. So there are plenty of incentives for motivated reasoning around the issue further mixing things up. If suppressors were just OTC safety devices I think we'd be looking at a different picture.
Ultimately though I think this is one of a number of medical issues that society overall is slowly waking up to right now (like plastic/"forever chemical" exposure) and will look back on with regret. Noise, not just from firearms but industry, equipment and just environmental exposure, has been under appreciated as a problem despite long standing concerns.
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0: the NFA requires checks, prints/photo, and a $200 tax stamp, so that's in the law and does add some hurdle. But the law does not require the process take an indeterminate 3-12+ months to just do the same look over and over again that happens instantly elsewhere. That's due to poor agency funding and procedures, but is one of the big hurdles.
Although I should note too that there is also State law: in 8 states suppressors are simply flat out illegal even if the federal government approved. So many people simply have no legal option period.
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Edit to your edit: It's worth doing the math for your own situation. Look at long standing NIOSH criteria for sound exposure limits by decibel, ie ( https://www.nonoise.org/hearing/criteria/criteria.htm ). Now go look at gun noise, ie., ( https://www.ammunitiontogo.com/lodge/silencer-guide-with-dec... ). Keep in mind of course that again, this will all vary significantly with gun, ammo, and environment. I'm NOT claiming that no usage of guns without a suppressor can be safe, again there are guns where 20-30 db less will be plenty particularly if used lightly outdoors. But that isn't every gun. Finally go look at anything on NRR (https://www.protectear.com/nrr-rating/) and maximum hearing protection. Keep in mind that factors like fit are crucial.
Then add it all up. If someone is firing a 165 dB gun while others are also firing 150-170 dB guns around them with non-custom fit hearing protection a doing a few hundred rounds once per week, what does that look like vs NIOSH limits? Play with the variables from there. And remember human imperfection. People forget earpro. Someone fires unexpectedly (safely downrange perhaps, hopefully not an ND, but still a surprise). Someone might wear earpro that doesn't fit that well.
So I personally will not shoot unsuppressed. It's just not worth it, the slightest hearing loss is going to cost vastly more money then a suppressor and stamp. It's some extra insurance as well in terms of earpro not doing quite as much as I expected. The long wait truly does suck and I can understand others just not wanting to deal with it, but I think it's an unfortunate state of affairs.
As far as artillery I think there what you might be misremembering is the level of instant hearing loss even with full earpro from even a single shot. If something is 180 dB then you need full head/suit protection or something else, earpro won't even get you below 140 dB at that point which means every shot = a bit more hearing loss.
Suppressors are also generally excellent at suppressing muzzle flash, moreso than flash hiders. Same idea as the tone thing.
They also reduce felt recoil impulse and muzzle climb, so controlling the weapon across a string of shots is easier.
A genuine downside is they make direct impingement platforms get really gunked up really quickly. Also, gas to the face via the charging handle. However, the advantages are so significant that basically nobody who has the option shoots unsuppressed. That includes most military forces; if cans suck why does everyone use them?
Re subsonics: that'd be true if you were simply underloading a designed-as-supersonic round, but a lot of the point of stuff like .300 blackout / .458 socom is to compensate for velocity loss with a fat heavy projectile.
Compensating (performance-wise) for velocity loss isn't easy, the "kinetic energy vs. momentum" isn't (AFAIK) settled, as every parameter (including projectile frangibility...) plays a role. My experience is limited, however when it comes to penetrating hard material with a metal-piercing round or to obtain a massive cavity (and shock) on a soft target with an frangible/expansive one, I will pick supersonic rather than subsonic-and-massive because there is too wide of a gap, just as (and for similar reasons) I will prefer a long gun to a handgun. A .300 Blackout (supersonic) develops (E0) ~1800J, while the subsonic version only develops ~700, this seems a "massive" difference to me, exhibiting the difficulty. "There is no replacement for (speed of) displacement."
Where I live, I can get a licence for a semiautomatic center fire rifle rather easily. So long as its not of a "military style".
So I can own a Mini-14, which fires 5.56/.223 rounds, etc, but not an AR-15 despite there being no functional difference between the two rifles. They both have the same standard magazine capacity, same round, etc.
The reason for this comes down to one being "military style" and the other looking more like a hunting rifle.
In the UK they are called "sound moderators" and are easy to get - you can even buy them for .22LR firearms over the counter if you say its for an air rifle.
In the US getting a suppressor requires a 200$ tax stamp, NFA registration, FBI background checks, fingerprints, and a huge wait for the ATF to process the paperwork.