Another option would be to choose not to behave in the sort of unethical manner that attracts the attention of Anonymous.

Claiming you provide "anonymity" when you don't (especially given the fact that some of their customers are using it to avoid persecution by oppressive government regimes who might kill them) is clearly unethical, and the sort of cynical capitalism-at-all-costs that draws the ire of the anons. Here's a thought: Put your customers lives ahead of your profit by admitting it isn't really anonymity they're selling.