Ok..sweet idea, but how are you going to make these people without passes leave if no one is to stop them from parking in the first place?
If there guys are already acting like jackasses at previous meets, I do not believe that them being told to leave will be received with compliance. They will probably say something along the lines of "who the fuck are you to tell me to leave?". Sure, the IPS guys can say they own the place, but I just don't see that having an effect on all of these dumbasses. Also, if some are being violent or have the tools to bring violence it could turn out badly. So, that leaves getting police involvement, which will not last for more than 1 meet I guarantee.
I am just saying. Some probably won't take too kindly to being told they have to leave if they are let in in the first place because they do not have a pass of some kind.