One unpleasantness I've noticed over the years on international flights is how confrontational certain FAs can be with Y pax standing up near the curtain. I once had a row 15 seat (first row of coach); I put my carry-on in the bin overhead the pilot rest seat, and a male FA rousted me when I got up to get something out of the bag mid-flight. I've occasionally seen them harrass others sitting near the curtain that they surmise might be trying to invade BE. They never seem to harrass pax on domestic flights in Y coming up to use the forward lav.