Perhaps they have been good stewards with what God has given them. If we start measuring the value of our pastor by how poor he is, then we ought to hire homeless people who have squandered all that God has given them to lead our flocks.
I suspect that my pastor makes more money than I do. He also works a lot harder than I do. If he was a lousy or a lazy preacher, then I'm sure his salary would be commensurate with his value to the flock.
The workman is worthy of his meat.