If you are too cheap or broke to tip then don't but using this as an excuse doesn't even make sense
Here is the link. Basically, there are people in FL are writing "no justice, not tip" or "your tip is justice for Trayvon" on receipts, IMO this doesn't even make sense, chances are, these people didn't tip before the trial, they are just looking for an excuse or trying to stir up trouble. I do feel bad for the waiters and waitresses who get these notes like this was their personal responsibility to get "justice for Trayvon". I mean they probably know they wouldn't have gotten a tip either way but still.
BTW this is not a should you tip or how much debate. I am just saying if you are going to be cheap and not tip (when the service was ok) don't make a stupid excuse that has NOTHING to do with the service you got at the restaurant.