I work for an Australian Bank. We had an internal competition where they didn't sanitise the data for this competition well enough. After a week of analysing the data one of the people in competing in the competition knew who's data we were looking at. It was a friend of theirs.
All identifying information had been removed/sanitised, they could tell from looking at the spending habits.
... So they knew, because they already knew. So really they just confirmed.
Ask that person to go and find my details, and they will surely fail. Because they know nothing about me, and the transaction history doesn't tell them anything... thus it is not 'identifying'.
That still isn't your identity. You can identify yourself by it, but no one else can. Unless they already know that information about you... it which case, they already knew...
All identifying information had been removed/sanitised, they could tell from looking at the spending habits.
I disagree with your statement.