If the investigators think that you are withholding data or harboring criminals, they can take the equipment. Bitcoins generally don't have the best reputation and they're a small company, so it's more likely they'll get treated roughly be the law if they don't cooperate.

Probably not because of one user, but when the cases pile up there's a good chance it'll raise questions about the legitimacy of their service.

When you earn your money by running said service, you are likely going to want to avoid that.