Rights don’t entirely disappear because a group of individuals decides to form a collective entity. That’s the heart of the Citizen’s United decision. If an individual can aggregate data about his customers and make a decision to not serve a known offender, then surely a group of individuals can do the same. That’s their right.

Again, this is not discrimination if it’s done for specific individuals, even if it’s done using data collected in aggregate. Banning a protected group wouldn’t be illegal. But banning a specific person would not.

Whether it’s legal to sell that same data as a list of undesirables is the open untested question.