Is this really scalping? He’s getting up early, using hours of his time and knowledge to select good knives, cleaning, repairing, sharpening then providing a selection of good knives for others to buy.
If you just want a decent knife I’d say he offers a good service that is cheaper and less risky than spending a day or more doing it yourself.
He reuses (or rather, rehomes) too by finding buyers for cleaned and sharpened knifes of good quality. That's a plus from an environmental viewpoint.
I dislike scalping where no real value is added to the service provided beyond getting there first, but this guy uses his skills to pick out good knifes, does quality assurance and presumably sharpening, and sells them with the ability to inform buyers about the type of knife and its intended use.
If you just want a decent knife I’d say he offers a good service that is cheaper and less risky than spending a day or more doing it yourself.