Inner doors should swing inward because in case of a fire or other emergency, you don't want to be trapped inside by something blocking the door that you cannot deal with. Even in something were preventing it from swinging open (like a rope or whatever), in theory the person could still get out because the door hinge would be located on their side and they could simply remove it.

Who has these door hinges that are so easily removable? I had to take a door off at my house recently and had to bash it with a screwdriver and hammer like 20 times.

A good poop knife will pop those babies out in no time.