Yeah, I think there's a line with bait fishing on one end and lures (including flies) on the other, and every fly fisherman figures out where they want to sit on that line, and how close to the other kind of fishing is "too close". Not sure if I'm making sense to anyone else.
Personally, I don't use scents nor do I think I ever will. I'd just pull out my bait casting gear and use that.