In the end it really boils down to common sense and courtesy- things much of country seems to lack these days. :)
I know a lot of guys who have harvested a deer because someone walked and or drove nearby and flushed an animal from cover. Those guys could care less about a quad rider and may encourage it.
On the other hand-
There is a reason many states require a hunter to wear orange during rifle reason! Do you really want to be that person (or have your child) flushing game for some of the folks that are out hunting?
On a personal note- We actually had a teenager pop out of the brush and point a shot gun at us just 400 yards from our hunting camp on Saturday. He apparently thought three of us returning to camp after a 14 mile hike sounded like a deer he was going to ambush. No one left that meeting happy!
