Because we let them get away with it. Take something they're going to miss and can't replace (e.g. their freedom or their head) and it will stop as long as enforcement is reliable enough that they expect to get caught.

These aren't good people, but if you make the fine to the organisation much more expensive than the expected return, lock up the whole board and leave their families without a pot to piss in we will see this become the exception instead of the norm.