Do you think your link shows that Facebook sold user data? Did you notice that Facebook wasn't paid and that the users specifically consented?

"We have to seriously challenge the claim by Facebook that they are not selling user data," commented Damian Collins MP, chair of the UK Parliament's Digital, Culture, Media and Sport Committee. "They may not be letting people take it away by the bucket load, but they do reward companies with access to data that others are denied, if they place a high value on the business they do together. This is just another form of selling."

Not defending what FB did in your example, but when you have to start redefining terms in order to make your argument, you're on shaky ground.