Google buys Mastercard data

Google has bought Mastercard credit and debit card records. Why on earth do they need to know so much about us? It’s kind of materialistic voyeurism and a bit creepy. How can it be legal for Mastercard to sell data like this? Why did Google want to spend money on this? Who’s idea was it in the first place? All these questions will never be answered in the public domain. #infosec