Hmm... Seems to me to be a way for you to justify losing to players you see as inferior. As Coaching32 points out, players need to learn to deal with that style and as Aloha points out, it's up to the parent/coach to reward or inspire the kid to play the right way.
You seem to be very jaded already and your kid is just beginning to compete. I'd be careful of attacking other players and their parents as it rubs off on the kids. Personally, I don't see so many "dinkers" and parents behaving badly. A few here and there, but generally I've seen pretty good tennis in the 12s and talked to many parents who have a great outlook on the sport. Is it your section or just your outlook? (Rhetorical, of course).
"More Sureshs, less Maxima for a better TT." - Power Player