T.S.
My son, no. But a lot of boys play it here, it's very popular. Most of the boys who play go on to play football in middle/high school, which is also very violent, even with all the protective gear!
I'm glad my son isn't into contact sports (he's a runner) but honestly, what are you going to do? All my kids have gone skiing, snowboarding and horseback riding, all high risk activities. My youngest did competitive gymnastics (lots of potential for injury there) and my oldest girl did club soccer (lots of chances to injure/tear the knee, as well as other things.)
I guess what I'm saying is they can't live in a bubble. As long as the program is reasonable, and follows good safety guidelines, let him play :)