Is there insurance for the payloads? I know very little about rocketry and launching satellites, but with the costs so high, I would imagine that there is some form of risk mitigation, but I've never heard of such a thing.
Yes, that is if you can afford it. The Zvezda service module for the ISS was launched without insurance or a backup because of financial problems. Embarrassingly they even had to turn to Pizza Hut for help:
edit: If I had read down further, I would have seen a discussion about this very question: https://news.ycombinator.com/item?id=9793697