While it was no surprise when Starbucks decided to implement Square's payment system into its stores it does come as one that Starbucks will now start selling Square card readers to customers at 7,000 of its stores in the US. They will be available for $10 with a $10 rebate for new users, this takes the total of stores to 30,000 that stock the readers. So why is Starbucks doing this? They came to a deal with Square worth $25 million, an agreement that also included the payment system being installed. Square is also expanding across Canada and is expected to hit Europe later this year.