I do it because deep down I think want to be able to fly. I have taken full scale lessons, but I just don't get the same thrill when I can't just go up and do anything I want to. (Like rolls, loops etc.) Now you could say, "you can learn full scale aerobatics", but when it comes to past times, I have a philosophy...
Never participate in any sport where the first rule is: DON'T DIE!