Seriously, I've had this question too. After reading on this board how people tip for everything, I went to purchase stones for a rock wall from Home Depot. A young man about killed himself loading several hundred pounds of rock into my truck on a hot day. I offered him a tip and he refused it and was embarrassed. It never would have occurred to me (before reading it here) that I was supposed to tip professional furniture movers etc., but not tip some poor kid who is working for minimum wage hauling stone in the hot sun.
Well, you let us know what Ms. Manners has to say.....as soon as you get the feeling back in that hand anyway!