Tedium itself is a heavy penalty. Most people wouldn't backtrack a long ways unless they absolutely had to. Most people won't do a tedious task over and over again unless they absolutely have to. Those who would, well, if that's how they want to play that's their business. Whatta ya gonna do?

This is true. The original Pokemon had a feature very similar to your church in the pokemon graveyard tower. There was a square you could walk into and it would heal your entire team for free without even making you go through the long (or rather, long when you had to read it every time you wanted to heal) dialogue at the centers.
But it was on the second or third floor and you had to deal with being accosted by ghost pokemon the whole way to get to it. In my own experience, it was wonderful when you were actually in the Tower for that part of the game because you may be getting your shit roont by the ghosts since there weren't a lot of pokemon up to that point that were good for fighting them, but it was too much of a pain in the ass to use regularly after you'd done all you had to there.
Especially since Pokemon also had centers in nearly every town that would also heal your team for free.
Is it still scumming if you recognize and embrace the reason why a player might return the church instead of trying to thwart it?