Occasionally, while you're slinging Root Beers around in Tapper, you'll notice that occasionally a patron will drop a tip on the counter.

If you grab it, you get a 1500 point bonus, and some 'entertainment' plays

But I typically avoid picking them up for 3 reasons:

1. Grabbing it takes you away from slinging root beers, which means that your patrons get closer to the end of their bars and tougher to get out
2. Some of the patrons quit paying attention to the drinks being slung at them, and when they start to overlap with each other, it can be tough to tell who wants a drink and who's watching the show (check out the bottom bar in the second picture, for example)
3. While patrons are watching the show, more patrons file in, filling the bar, and making it tougher to clear the level

This doesn't mean that you should necessarily avoid grabbing all of them, but I'd avoid them until you're ready to increase the game's difficulty.