I don't "expect" anybody to repair my caches or caches that others place. That's not the point at all!
My "expectation" is that a thoughtful cacher will carry a spare log or two and replace a log that clearly needs replacing. I agree with LT that replacing an entire cache that you deem is missing is irresponsible.
But replacing one that has clearly been destroyed should be encouraged. That happens and when I'm headed out to do a cache that the previous cacher indicates needs replacing, I'll replace it. Anybody think doing that violates the spirit of the game? Brad, didn't you guys find one I replaced on top of a mountain not that long ago?
Sometimes the road less traveled is less traveled for a reason.