It's standard profit maximization. If you can get a customer to pay $X, and then also sell their data on the side for $Y, then why wouldn't you do it? Generall

It's standard profit maximization. If you can get a customer to pay $X, and then also sell their data on the side for $Y, then why wouldn't you do it? Generally, people are prohibited from reselling the things the common items of our existence: electricity, internet service, food, and so on. Businesses have no such restrictions, even though like food, personally-attributable information can be put to harm.