any time i have worked at a place with a dress code (and there have been many) no matter what it is, someone is trying to push the limits.
when it was black and white, there was always someone showing up in dingy grey/white shirts, ragged walked on trousers, or tops either too low cut, dresses too short.
sneaker day, there was always one or two who would show up in uber ratty, dirty, sneakers.
the manager always had to decide, send the employee home to change, and be short staffed, or they could buy something off the floor. (if they had the funds to do so)
it was a on going battle. always seemed to be the same people too.