Midway Arcade Origins

Press the button one to fill, and once more to slide it down the bar. Run right to collect empty mugs before they fall off the end of the bar. Move up and down the 4 bars, filling and sliding as you go.

It is possible to get most, if not all of the 25 customers on the first level if you drag it out.

I progressed through levels as usual, getting to the third level and only losing my first life right after the achievement popped.

Managed to do the whole achievement in the first level, just keep the one guy on the bottom row, and do the upper three starting from the top when they start and keep appearing, you'll get three at a time that you'll send out the doors on the left, plus one or two at a time for the bottom row guy keeping him around, as long as you sling the root beer at him once he's past the halfway point of the bar, he'll stay active and not disappear out the door on the left. After you've sent about six rounds of the three upper rows out the door, you'll have done enough to keep the guy on the bottom row around as well and served him around seven or eight mugs of root beer, and the achievement will pop AS LONG AS YOU'RE IN SCORE ATTACK!!!