And this only works if you have a lot of other data in your data set. If you don't know who Scot is, then you can't figure out he's the only person who could go to the bakery on that one exact day and that particular restaurant the next.
I don't think anyone is particularly sanguine about the future of privacy if big companies manage to figure out a way to profit from combining their multiple massive databases. This is particularly true in the US, where it would be virtually impossible to stop the police from using said databases with our warrants. Or worse, using info that the big companies forwarded them as the basis for warrants.
If Apple or Google can silence one of it's critics by figuring out he was paying a hooker with his supposedly anonymous Mastercard gift card, that is a really fucking bad thing.