I just have to ask, would you care if a local cacher went and retrieved all the bugs as soon as you put them in there, all the time, every time? I'm sure there's a lot of people who would do that, seeing as it's just a prison, as you call it.
I really would not care. Its just a game to me. If I called this a Travel Bug Resort with a lake view, no one would get upset but the location, concept and design would all be the same.
Of course you would care. If you go to all the work (fun) of designing and setting a hotel cache, it does matter that someone empties it, leaving nothing for the next poor cacher. It's a matter of courtesy.