Interesting. I have been renting since the early 2000s, and I've moved many times since then. I can remember 9 different rentals right now, but I think there were more I'm just not remembering at the moment. All of them were in the area of Milwaukee/Madison Wisconsin.Every apartment I've been in has an upper deadbolt that can only be opened from the inside.
I never had an apartment door that did not have a deadbolt with key access to it from outside. So I guess I just assumed that's how they all are.
If I were an owner of a unit, I'd personally want to have all locks accessible to me. I would not legally be able to enter whenever I want, without proper notice, so making all the locks accessible doesn't deny the tenant any legal privacy.
Anyway, it's a stupid problem that had stupid repercussions that you had to deal with. I'd be just as upset.