I just can't understand this - the places I've been, if I'm not at the chair, the only place I'd want to leave stuff unattended is the unit. If they added lockers - which I really don't understand why that wasn't done a long time ago - then those could be OK too.
IDK to me it's like, don't leave your crap in public places. Take it with you. Get a wagon I guess if you need that much stuff to go to a pool.
I mean, personally, move your feel lose your seat. But that's what I've been used to at home for decades now. If you're not using the chair, someone else should be able to use it.
I'm willing to suggest a quick bathroom trip should be OK, but I also know people who would find 45 minutes potentially a bit short for a bathroom break, and again, there's only 24 hours in a day, of which I bet there's like 8 hours where this is a big issue? So it seems like wasting 1/8 of the potential usage is quite wasteful. Same for swimming in the pool, if you're in there for like 10 minutes, fine, but as you approach 1/8 or more of the potential use of the chair seems like bad manners to me.
Why would you think you can keep a free space while off doing something completely different? Do you get mad at someone taking your parking space when you nip out to the local grocery "for only 1 hour"? IDK, I don't see the argument here. You're either using it or you're not. Simple. I'd suggest paid lockers or expensive paid chairs if you want to reserve them "just because" - and these probably should be add on hopefully paid for by people who want to have a chair "just in case" or as a strange location to keep stuff.
Yes, I suggested a rather simple key based system, but that's a lot of tech to make it work. It'd probably be an expensive per hour fee to pay for the system and maintaining it for those who wanted to reserve empty chairs.