Take your time in the first few levels. You can
make a high score by leaving one person and waiting
for more people.
The last guy in the row will almost always leave a tip.
If a person leaves the bar in the first level you get
50 points but, if you let them get close to the end of
the bar, they will drink the beer and stay. It's 100
for getting the empty mug.
The longer you stay in the level, the faster the people
and mugs move.
Here's a Tapper Easter Egg. In the attract mode, wait
until the word Tapper is filling up with beer, and hold
down the joystick, both taps, and the player 1 & 2
buttons. You will then see the names of the game