Re using radio scanners, back in 1968 when I used to go spotting a Lulsgate the satco there had a strong dislike for people listening in to the tower, anway one day while I was sitting down with my earphones in listening to radio one I was approached and questioned by two men apparently from the Post Office they had been sent by said satco he was most upset to find I wasn't tuned in to ATC.
Btw being interested in aircraft led to one of my mates becoming an air traffic controler and the other an airline pilot and me bottom of the pile a fitter at Bac Filton.