Memories of using an air mattress are when sleeping over at friends places being drunk and hot and the stupid mattress wraps around me as I sink in it and my body heat just heats up the whole thing and I woke up all sweaty.
Well yeah if your air mattress has a leak of course it will deflate. I slept on an air mattress for an 8 month internship. It was one that had an integrated pump and cost a pretty penny but it was great. Never deflated unless I wanted to make it softer.
It's not, you will not be perfectly balanced in the center while you sleep, you will end up tilted comically one way or another. Probably with your head below your feet.
I just spent 4 days in a camping for a festival sleeping in an air mattress, and it was fine. Maybe buy better quality mattresses or take better care of them? Mine has been to plenty events and it only deflates a little bit after 2 days of scorching hot in the tent-oven, which is normal.