Just because you can think of ways out of enforcement doesn’t mean all enforcement is impossible. If there’s a plumbing truck parked at the movie theater, management is going to damn well know if plumbing work is occurring. I know it makes us feel smart to think of loopholes but we don’t need airtight enforcement in order for a law to make sense. There are tons of laws on the books that aren’t actively and exhaustively enforced, and the exist to give authority to those who would take action.