This is a pretty puzzling idea to me. How could linking something be theft?
To explore this, I shall try a metaphor. Imagine you're on a big social media website (lets call it Programmer Olds) which has an oddity in that 99% of its users use adblock. You then post a link to another small (ad supported) website on your Programmer Olds page, causing a large number of people to click through and download the page using large amounts of bandwidth (for no monetary gain to the site) and possible DDOSing the site.
Have you commited theft?
The difference here is that while a lot of users use adblock, there are some that don't. These users can still see the ads. Additionally even though it's a small website, it may lead to new readers that stick around or the content itself may even be sponsored.
The equivilent to hot linking a picture would be like taking the content of a blog post without really linking to the source, because there's no chance of conversions there. If you're linking to the site itself then there's a reasonable chance that users can convert.
So I suggest that it's theft just because the chances of readers being converted is nil while you're using their bandwidth.
That's because you're responding to an entirely different issue. "Hotlinking" isn't linking to something, it's including a resource that is hosted elsewhere. It's putting <img src="https://concordDance.whatever/images/big_image.jpg"> on my website without asking you. Now if my site ends up on the front page of HN, that could cause a lot of traffic to your site, potentially overwhelming your server or increasing your hosting bill. It's not nice, and rightfully frowned upon.
In both cases the site loses bandwidth for no gain due to your actions.
If I tell the customer they can go next door to get a panini, I'm not stealing anything. Maybe that restaurant is packed right now and they'ed rather not have an extra customer, but there is a reasonable expectation that they would generally want customers or at least have a means of turning away unwanted customers otherwise.
On the other hand if I break into my neighbor's restaurant, make a panini, then bring it back to my restaurant to serve and make money off of, all without permission from the neighbor, I am most definitely stealing. Even if I doubt the neighbor will mind because he let me come over and make myself a panini once, I can't unilaterally act off that assumption.
Of course when someone doesn't want us to hotlink to their assets then don't do it.
[0] https://commons.wikimedia.org/wiki/Commons:Reusing_content_o...
it's not theft if you leave it out for everyone to use.
But you can totally sue anyone for anything, and that makes for entertaining headlines - even though if plaintiff lost promptly
It is possible this principle applies to other countries and other things than pools.
I wasn't sure if it is the same or similar principle in Russia or a different one that requires active care for a burglar. Unlabeled chemicals causing liability for a burglar seems extreme to me
However my favourite example is the law that allows any bee keeper to enter any private property if they are pursuing fleeing bee swarm.