I know the tale of dented corners all too well. Working on my mirror frame for my vanity last night I knocked the same board off the back of my bench twice, only one dented corner though. Of course it is on the face side though... Maybe I can trim the dent off. Maybe I'll try steaming it out, not sure if that will work on a corner though.
In all fairness, that helper has a bill rate too. And it is probably a lot higher than $15 an hour if he sent him out on his own to a jobsite even though the helper probably does not even make $15 an hour.
I guess there is a market for it. Most people have no idea how to use or sharpen hand planes (or that they even exist). I had no idea they were useful once, but now I can't imagine not having a sharp plane in the shop. I don't think they were even mentioned in high school woodshop where they could have come in handy many times. They are great for all kinds of small tasks.