Are you infinitely wealthy? Storage units are a slow leak on finances, just like uncanceled subscriptions and mobile phone plan features.
It's far cheaper to use a storage unit for a lot of this stuff I do routinely use than buying and selling a house just to get more storage space at home.
I'm not blind to the fact not everyone just stores junk they never use. I'm certain there's a percentage of stuff in mine that is probably better off sold or trashed. But until we stop changing decorations for the different seasons, stop a number of hobbies with bulky stuff, or move to a giant mansion I just don't have the space and could use a few more square feet of pure storage space.
Every square footage of every home costs $$$ to keep in your possession. I pay a mortgage. I pay insurance. I pay taxes. I pay maintenance costs. There were acquisition costs in the purchase of it, and there will be acquisition costs wherever I go next. Not one square inch of my home is "free".
Suddenly that simple answer isn't so simple when actually confronted with reality, unless you're willing to be homeless and just carry your possessions in your hands.
So "free" as in "ignoring actual costs" and "ignoring opportunity costs".
Storage needs can change quite a bit over time. Household sizes sometimes change over time. Hobbies can change. Lifestyles can change. What was more than enough storage space several years ago can become not enough later on. Buying a bigger house to have more "free" storage space isn't really "free", especially as interest rates have increased massively over the years.
For instance, in the past my needs for storage for "camping gear" was largely handled by a single big backpack. Its just me, I'm down for pretty light camping. Now I've got multiple different sized tents for different kinds of trips, a sun shade, a whole family's worth of camping chairs, folding tables, camping stoves, multiple lanterns, camping related toys and activities, far more water storage, etc. What was easily stashed in a corner of a closet is now practically its own shelving unit.
I have to regardless of a storage unit or in a closet in my house. That closet in my home and that shelf in my garage isn't free either.
So then it's just a question of owning anything at all or nothing, because it all has a life long recurring fee for the privilege of continuing to own it. And yes, my family finds value in decorating for holidays as a part of celebrating, remembering, and keeping traditions alive.
Sometimes people don't just want to live in the same IKEA box 365 days a year.
Your standard also doesn't make much sense. Garages can vary from barely being able to fit a compact car to having like a four car garage with a workspace area. You're saying that for both instances that's just perfectly the right amount of storage space for those people? The person with the small garage just isn't supposed to have any of the same hobbies as the person with the giant garage?
I guess I could just get rid of all these tools though. Every time I need something fixed I'll just not do it myself and just pay others instead of just doing things myself. I guess I could also just give up on a ton of hobbies we have. We can just throw away our family traditions that have been passed down for over a hundred years. I'm not wealthy enough to live in a house with enough storage space with the other constraints about where I'd like to live, so I guess I just don't get to have these hobbies and traditions and heirlooms.
Or I can just spend like $500/yr and still manage to keep all these hobbies and traditions and heirlooms.
I don't have space issues because I do get rid of stuff and I don't buy much stuff but I still have a bunch of stuff I would throw away or sell before renting a storage.
It seems hard to imagine the sums involved becoming comparable to other amounts of money lit on fire to avoid fights with family though (i.e. home renovation, travel).
Are all these comments like yours coming from college students or what? If anything else, a storage unit is one of the most valuable things to pay for if you just moved out on your own.