The one finger wave or the choked fist used to be the extent of my vocabulary.
I have gone to indicating my displeasure with a thumbs down gesture. It's not vulger and doesn't seem as likely to result in a confrontation. Some people will react strongly and unpredictably to any negative comment about their actions.
It's generally not good to get "mad" in public. A little frustration is bound to happen, but no need to get "mad". Not everyone on the planet is as smart, considerate, and blessed as you are. Try making some allowance for those of us who aren't always "fully qualified for lifes events" or are not always at the top of our game.
1998 Silverado 6.5 Turbo Diesel, 4X4 K2500
2003 PT Cruiser