When flying near a town or village, it's usually pretty easy to find a field or open area that borders the town and do a display over that particular bit of earth. From the ground it may look directly overhead but actually isn't. Aerobatics are best seen from the side, not directly underneath anyway, and most aeros pilots know this. There's not much to be gained from flying "directly overhead" so few people are actually likely to do that. "Very nearly overhead" may actually be over a nearby open field.