You're describing the rarity though, not the norm. And that's kind of my point, an uber talented kid ends up at a private - everyone gives you the proverbial sigh and moves on. Same kid ends up at an out of district public school, people raise questions, they contact OHSAA, everyone virtually throws a fit. That's the difference!
I'm not sure what happened with the Decatur's and why they didn't end up at Wadsworth - but if I was just making an assumption, it'd be that there was eligibility questions, potential sit-down requirements for transferring, etc....all the red tape and hoops I previously mentioned that discourages public school transfers/recruiting. Where were they originally from? Why didn't they end up going to Wadsworth?
And you can argue till we're blue in the face that it happens with Publics, where kids transfer in. No one is disagreeing with that, we all have examples of it happening. The difference is, MOST public schools don't have kids transfer in for athletics, and the occasional few that do get those sneaky transfers - it's usually 1 maybe 2 players. Whereas there are privates who have entire starting lineups of those transfers. Thus, the need for competitive balance.