The guy sharpening knives - would he do it right there on the spot? (I’m guessing he did if he had the stone with him).
That might even work today still. We have a set of nice knives that they will sharpen for free. Except you have to ship them back, wait weeks, etc. The local store will also sharpen them - two at a time. We’ve never done either!
I’ll sharpen one of them - but my wife doesn’t trust me with the others!