I bussed tables at an expensive restaurant when I was about 15... The waitresses did not split tips, but they would put a few bucks in an envelope to be split up among us bussers...
If you were REALLY good one of 'em might pull you aside and slip you an extra $5 or $10 just for you... I figured out pretty quick who was apt to do that and I made darn sure I helped to take care of her / their tables the second they needed anything!
