You don't get to tell site owners what to do. The actual facts on the ground are that they're trying to block your bot. It would be nice if they didn't block your bot, but the other, completely unnatural and advertising-driven, monopoly of hosting providers with insane per-request costs makes that impossible until they switch away.
You wouldn't have to make them micropayments, you can pay out once some threshold is reached.
Of course, it would incentivize the sites to make you want to crawl them more, but that might be a good thing. There would be pressure on you to focus on quality over quantity, which would probably be a good thing for your product.