Don't touch people you don't know, even if you're "just trying to squeeze past."
To the older gentleman at the Skokie Farmer's Market this morning who didn't like being told to stop touching my back: DON'T TOUCH PEOPLE YOU DO NOT KNOW.
I wasn't rude for telling you not to touch me, YOU were rude for touching me. You saying "excuse me" doesn't make it acceptable to place your full hand on my lower back and oh so gently push me out of your way. Use your words, not your hands.