That's how I was when I was coaching a team. I used to say at least if they went to somebody else I couldn't be blamed if they didn't perform.
I would try to learn what their coaches had told them to try to help as much as I could. Often, though, I'd just ask "What does your pitching/hitting/whatever coach say when you're doing this?" Usually it was enough to get them on track.
There were a couple of times with kids who were just early learning when I'd take a parent aside and suggest they were not spending their money wisely on lessons. For pitchers that usually meant HE and slam the door. I'd tell them you don't have to come to me, but if you want your daughter to succeed you need to find somebody else. And I meant it, although of course they'd come to me. For kids that were deeper into their journey, though, I just let their performance speak for itself.
Ultimately, like any coach, my goal was to win games. To paraphrase the movie 42, I'd let an elephant pitch if I thought it could win me ballgames and I'd bench my own sister to do it. Whether they were my student never really entered the picture. Well, it did one game because of a particularly troublesome parent, but only that once. And I'm sorry it happened then.
