> If this is Earhart's plane, it's probably also her grave.

Only because no one knew where she was to bury her properly.

I assume you don't say that we shouldn't recover bodies from ANY plane crash; most people would expect bodies to be moved from a plane crash to be buried properly.

Why is this one different? The length of time it took to find the crash, I assume. So how long before we can't move the body because it is a grave? 3 months? A year? 10 years?

I don't think I would consider this a grave, and recovering the body and burying it properly is not grave robbing.