engine - 2:47 pm on Oct 25, 2011 (gmt 0)
Oh, they already track your purchases, even if they aren't doing anything with the data.
It's just a question of marrying the two sets of data and making it work. Not easy, but much more doable these days.
They will slip this through in one of those, "we've updated our terms and conditions..." messages that is in small print.