This is true but not super relevant to the question of whether paying someone to place an ad in front of certain demographics is selling information.
Because sure, Google knows a lot of people and they have a lot of ad space to fill which means they have a good chance at finding and reaching the demographics I asked for but I don’t get any of that information as part of my transaction with them.
Does it really matter if the data is technically being "sold" or not? The fact that any one entity holds an unprecedented level of information about us is alarming in and of itself. As Snowden said in his first interview, all that data is just sitting there waiting to be abused, and the only thing stopping anyone from doing so yet if they haven't already are policies that can and will change in the future. It doesn't matter who has access to the actual data as long as someone does.
If adtech wants to serve us "relevant" ads, that's fine but the intrusive spying has to stop. Plain old contextual ads should be more than enough for that purpose.
Because sure, Google knows a lot of people and they have a lot of ad space to fill which means they have a good chance at finding and reaching the demographics I asked for but I don’t get any of that information as part of my transaction with them.