Tip the can smashers? Not what I usually do....
I have found articles like this to be kind of helpful on who to tip though.
When To Tip? And How Much?
It seems like more places are building biger tips in to their bills. Not that I don't tip but I like to determine how much myself based on the service. If someone is just doing their job and nothing else... NO GOOD TIP FOR YOU. But the bill in most restaurants now have an 18 or 20% gratuity automatically built in to the tally. Slipshot Sally who spilled the drinks and sneezed on the pasta gets her tip just for doing a bad job.