Some people brought up them getting sued for not blocking them but that doesn't make any sense, since you have to intentionally connect to a server to access any site. It's not like people accidentally type in the address for a very specific site then blame it on someone else. Doesn't really make sense.
Having worked with various businesses it's less about religion and more about money and bad press. Anyway, they're well within their rights even if I don't agree with them.