I give anonymously all the time. Saves the argument and the inevitable "I can't take this".
I passed up a chance for a $20 bill giveaway. A man approached me as he hung out (what will Spaw do with that?) the passenger seat of a double stretch limousine bidding me to come over and take the money. I remembered the first thing my mother taught me - "Don't go near strangers in cars!" and refused. Turned out it was a local radio station promotion. Ah well.