I had this happen to me at a fast food restaurant a few months ago. I guess my dogged, suspicious nature of my fellow humans must have kicked in a little too soon. I pulled thru the drive thru, my bill was something like 8 bucks or so. I had my cash in hand, ready to pay when the sixteen or seventeen year old girl at the window says "You don't have to pay for your food sir, the person in the vehicle in front of you paid for it." My first reaction was to check the truck in front of me for familiar people, a co-worker, friend, something like that, but I didn't recognize the vehicle or the person as they pulled away. I asked the girl why they paid for my food. She looked at me and said, "They're paying it forward, that is the fifth vehicle now." I asked her what that meant still trying to figure out who was in the truck in front of me. By this time, I'm checking behind me to make sure this isn't some sort of mafia hit or the girl at the windows isn't pulling a silenced pistol or something from behind her back, I know, too many Godfather movies....anyway, for some reason, the pay it forward concept just isn't computing. I held my 8 bucks out to her and told her I'd like to pay for my food. She told me "You can pay the bill for the car behind you, it's $25.60."....... The SUV behind me looked like it was full of soccer kids or something. I just chuckled, handed her my 8 bucks and told her to do whatever she wanted to with it. I guess I just don't get that concept. I ran it by wife who laughed and told me she wasn't surprised I didn't participate in the pay if forward gesture. She told me "You always see a scam or an angle in everything people do, I don't even think you realize it anymore." I thought about that for a few minutes then asked her if that was a good thing or a bad thing.......She just laughed and told me "One of us needs to be like that I guess."