^ haha i would like to know too. the majority of ball sports on grass the players wear shorts but Baseball and American Football players seem to wear pants?
I'm not an expert, but in baseball, I would assume it's a safety issue, as players may need to slide into base.
Yeah the infield dirt sometimes has rocks in it, and believe me in shorts you get some nasty cuts and burns.
I agree with the OP I've NEVER seen anyone throw without the laces before, I always have, and I have big hands. In american football you are supposed to spiral the ball (to get the max distance out of the ball) every time I have no thrown with laces it get the "wounded duck" properties. However, it could be why those two QBs are still in college