If no one gives him feedback, he will assume his dad is right, and keep ignoring customer requests. How else but by feedback can he learn that his dad is wrong? Or at least that his dad is losing business. Probably including the o.p. But without feedback, he doesn't know it.
He will also have trouble breaking into the higher priced sharpener market, because that is mostly careful custom work.
BTW, one mistake some hockey-trained sharpeners make on figure skating blades is to take off too much steel, sometimes over .01"/sharpening. Most hockey blades are cheaper to replace than most figure blades, there is no toe pick to mess up the profile after too much steel is taken, and hockey play often creates deep nicks in the blades, so removing more steel makes more sense for hockey than figure skating. Usable blade lifetime is inversely proportional to the amount of steel removed on each sharpening, unless you break your blades, or out-grow them, so it is better to remove as little as needed to create good edges. Say, .003"/sharpening on a good powered machine tool, as little as .001" with good hand tools if you are very careful.
the other hockey place which is reported to do good sharpenings. It just entails an 1 1/4 hour drive
1.25 hours isn't a lot, by many skaters' standards.
Maybe the knowledge that a better sharpener will likely remove less steel, and your blade will last longer, will convince you they are worth the extra time and money?
O.P., if time matters to you all that much, learn to do your own. Unfortunately, last I knew, the most common good quality hand tool, the
Edge Specialties Pro-Filer, isn't available in 7/16". Much like the bad sharpener, they nominally sell 7/16" sharpening tools, but by their own admission, if you call, they are really cut to 1/2"! They do sell 3/8", which is sharper. Though there is a significant learning curve, to record and maintain the original rocker profile, and keep the edges even. You
will I've made home-made sharpeners at about 7/16" by gluing sandpaper to 3/8" dowel rods, and using a strap of leather or similar material to help me center the sharpener on the blade - but that requires an even longer learning curve, because it is harder to center that way than by using a gapped handle like Pro-Filer uses. If you learn to do your own, you will probably never go back. Not only is it cheaper to do your own, and may involve less driving, but you can get exactly what you want, can produce a sharper effective edge, and will probably waste less less steel per sharpening.
I admit that few figure skaters sharpen their own. Maybe I just enjoy learning to do stuff with my hands, because I wasn't taught to do that as a kid.