Whatever you let slide at practice is the real rule. The posted one is decoration.

Rules are set by what gets tolerated, not by what gets written down. The moment a standard is skipped without consequence, everybody updates to the new version, and the sign on the wall becomes something people walk past. You are making rules all the time, including on the days you are tired and would rather not deal with it. Enforcement is the whole message.

Pick the one standard you keep letting go and hold it this week, starting with yourself. Say once that it is back, then be consistent rather than fierce. Drop the rules you are never going to enforce.