First off you do earn stars. I know this for two reasons. First, the number on the back if the Starbucks card goes right to the Starbucks computers, so they know you were at a Starbucks. Second, I had not used my card in about a week and all my stars were current. Then I go to DCA and get a iced green tea. Next day a star is there. So yes you get stars. Also you can not scan app. I asked, and nope. Just like my Starbucks at LAX (I work at LAX) you have to have that card. That is my experiences. Your mileage may very.
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