I was too! I once pushed my stepson right over the pony "helping him get on"! We had some fab videos, but a livery took them to put on a disc for us, and never gave them back.
It gets worse when they're off the leadrein. We videoed my stepson doing gymkhana races and there was a pushy mother screaming in the background. I shortly realised it was me! Had to ban myself from the sidelines!