What kind of wackjob will sit in a restaurant and video you for hours? Is he spending money while he's there? Definitely something wrong with him, creepy is the best word I can print here.
Have the manager tell him this is a restaurant and the entertainment is for the pleasure of our guests. His videoing is disturbing because as you wisely said some prefer their privacy.
I've helped move tables and chairs, move boxes out of the way blocking the entrance to get my stuff in and even helped change a few kegs for the bartenders but rest room duty, they're not paying me enough for that LOL!