But we don't agree in advance to give up our attention in exchange for things. Nor do advertisers feel obliged, per se, to give us something in return for looking at ads. It is simply assumed that we don't own our attention, and it is up for grabs to anyone who can get their hands on it.

We expect to see ads in many situations, but only due to past experience, not because we ever made a deal with anybody.

And the most effective ads, the ones that advertisers strive to create, are those that are the most unexpected.