You really have to be assertive in those situations. Stop what you're doing on the spot, Look him dead in the eyes, go from the smiling waitress to the very serious look on your face and say with a stern and LOUD voice "Please don't do that EVER again, if you do, I'll have security escort you out!"
That's it, it will work. Don't worry about "making waves". They know they did wrong and won't give you shit about it.
Do it.