Having a consumer download a sketchy file from what should be a trusted service (it's firefox! they're the good guys!) is not good for your company image, either.
And unfortunately, charging for a service is no guarantee that these issues will go away. I have seen fraud links from many b2b services presumably caused by credential misuse. If you operate a file sharing service, please be sure that there is a way to report a file either on the download page or on the contact us page. I'm the guy with too much time on his hands and actually follows up on reported phish emails and I've seen many services with no reporting mechanisms. Also, give your customers their own subdomain so I can selectively allow them in the palo alto.