Don't think anyone is going to get confrontational unless he's fishing illegally. They might sneer or think bad thoughts though.....I know I always do.....lol..... just kidding. Even die-hard walleye guys can learn to fly fish though.... loan him a rod and teach him how to do it right.A dyed in the wool, MN North Woods walleye fisherman. You should see the looks I get when I whip out a fly rod up there! (You can walleye fish with a fly rod. It's pretty stupid. I do it anyway, because I like it )
The difference between swinging a weighted streamer on a fly rod and swinging a small Mepps on a spinning rod seems mostly philosophical to me...but snobs will be snobs.
He mostly wants to know if they'll just sneer, or if they're likely to get confrontational.