Actually, it seems like much simpler than that. Possible, but unlikely: the pizzeria was using a tracking pixel with a purchase event and was targeting ads to

Actually, it seems like much simpler than that. Possible, but unlikely: the pizzeria was using a tracking pixel with a purchase event and was targeting ads to friends of purchasers. I don't think you can do this exact kind of targeting (but not sure) and it's pretty sophisticated for some random pizza place. By far the most likely scenario is a mix of coincidence and confirmation bias. The pizzeria was just running geo and time of day ads and your friend did not notice or remember until this event made it seem significant.