At the school I attend, there are a lot of professionals. But at some of the schools I have been at, you get a lot of tough kids from poor backrounds. One of the reasons I switched, was to attend a more BJJ oriented school with people who have to go to work jobs the next day and don't want to be tested by every 19-21 year old punk who wants to make a name for himself at a small show. BJJ, although very physical, doens't involve getting kneed and elbowed from side control, or having a knuckleheaded polynesian kid pick you up and slam you from a triangle attempt. Sparring is one thing, thinking it is cool to have constant black eyes, or getting your nose broke aint my cup of tea anymore. I'll stick to sub grappling and BJJ.