The solution to #1 is obvious but expensive. The solution to #2 is to hire more people, which is obviously difficult, but raising wages to solve #1 would probably help here too (I'm guessing they don't even want paid time off, just time off, so there's probably some additional expense involving more people but not strictly wages).
#3 seems a bit trickier. Corporate home office can't do a lot about the public being jerks. The only thing I can think of is empowering staff to kick people out for bad behavior, but that realistically that means hiring security staff or calling the cops a lot.
Of course I'm just speculating, I don't see any of this changing anytime soon. Clearly there are still plenty of customers at this theater, which is what the company cares about most. Until a staff shortage starts hurting profits nothing changes.