I'm apparently a fast harvester/plower-I've had several people who've hired me comment that I'm speedy. Guess my mouse finger muscle is extra strong.

A lot of times when I get hired to work on a farm with someone else I end up harvesting/plowing more than half of the farm. I don't go after specific crops or anything-just start in one corner and work my way towards the center.
Recently I've had a couple people that I've harvested with (the other harvesters-not the people who've hired me) accuse me of being rude or selfish-I assume because I did more than half.
Am I supposed to stop at the halfway point on the farm and just stand there until they're done? I was operating under the belief that we were there to get it done.
So what's the reigning FT etiquette-am I being awful?