He doesn't just 'support' Q, he is behind the entire operation. I'll let you figure out why the ban of Q gear at rallies. Put that big brain to work. I can't do all your thinking for you.

Because Trump thinks Qtards are a bunch of gooberheads.
Last time he called, he said y'all were a drooling band of geriatric crotch-pandas.
He's got a way with words.