The problem isn't giving quality instruction for a price that you feel is worth your time. The problem is when Coach FewExtraBucks starts letting his small business get in the way of his judgement. When it is neck and neck between two guys for a position and the guy who spent $1200 in lessons in the offseason gets the starting job because he knows the parents will sign him up again. Or when Johnny HittingLessons keeps pinch hitting for the starter even though he is hitting .200 on the season. That is when it starts to get ugly
You see it all the time in travel, the kids who take lessons at the academy are often awarded more chances than the kids who don't do lessons and just play. We were part of that one summer, it was obvious. Kept quiet and moved on at the end of the season. Watched that very good team fall apart by the time they were 16.
Our HS coach had a travel organization. He took players from the school, charged a pretty penny, and played a weak schedule full of local tournaments. A lot played, but some didn't. We never had to worry about this, but there was another kid who played for a cheaper rival organization. It was fairly obvious the kid had more talent than some of the kids who played for him over the summer. He didn't see any meaningful innings until he was a senior when most of the coaches travel guys had already graduated.
Unfortunately for every guy who knows what he's doing and does it the right way there are 10 more who like you said, agree the HS HC job doesn't pay enough and use their title as coach as a business opportunity ahead of it being a making my better players better for a few bucks situation.