i played soccer for 5 years and i NEVER saw anyone get hit in the head by anything. this sort of wussy parenting is turning our nation's youth into a bunch of nancy boys. i remember one of the goalies on the first team i was on got smashed by about 3 other players. today's kids would cry for mommy (i have seen it many times), but that guy just stumbled up and stayed in the game (BTW he was about 6). and that was only 13 years ago.
EDIT: if me kid ever runs up to me and tells me that some kid hit him, i will respond "well hit him back, ya nancy boy".