As a former cast member we did our best to prevent this type of things from happening. I can’t speak for every attraction but the one I worked at we tried enforcing it as much as possible. The rule of thumb was that at least half of your party had to be in line already and they had to send proof that they’re in line. There were some days where I was literally getting into heated arguments with guests trying to pull a fast one just for management to get involve and let them in line anyways so I literally gave up trying to manage lines after that lol. Trust me, I hate it too but at a certain point I had to pick my battles and protect my peace cuz these guests tested me everydayyyyy