I've never been contacted to sell user information, but I have been contacted to purchase information. Before I purchased whois privacy on my email's domain, I

I've never been contacted to sell user information, but I have been contacted to purchase information. Before I purchased whois privacy on my email's domain, I was frequently propositioned to purchase lists of users and emails relevant to information security and general SaaS products. It was pretty sad, actually. The emails never explained where or how they got the list of users, they just promised I would have an incredible ROI from these "qualified leads."