When I worked at Starbucks years ago, I saw this happen a lot!

Once at Chik-fil-a, the person in front of me paid for mine, so I paid for the person behind me.

Apparently in Houston, it happened 67 times one night at a Chik-fil-a!

http://www.click2houston.com/news/fast-food-customers-pay-it-backward/-/1735978/22623004/-/12842on/-/index.html

This just gives me another reason to go to Starbucks this afternoon...to be nice to someone!

ETA: We had one lady, when I worked at Starbucks, buy a $10 gift card on a regular basis and tell me to pay for as many people behind her that I can with it!