There is another unwritten rule : if you do something that is deemed disrepectful in the locker room, fellow pro-wrestlers can ban you from changing in there.
The ban can only be lifted by the one who imposed it.
Which reminds me of that odd time when The Miz got kicked out of the locker room by Chris Benoit for eating chicken over referee Scott Armstrong’s bag.
The latter noticed it and said, "Dude, you just got stuff all over my bag." A furious Chris Benoit came in and went, "You are not allowed to dress in our locker room. I think you should just stay out of the locker room."
The odd part of the story is that, after a while, Benoit committed suicide, so he obviously could no longer lift his ban on The Miz

Fortunately, The Undertaker ( a vet and a backstage authority ) later noticed The Miz chamging outside the locker room and said, "what are you doing here kid ? Come back in."