Not being a Starbucks guy, I'm a little ignorant of the Starbucks etiquette, in fact I find the whole thing a bit intimidating, and I can never figure out how to order an extra large without being looked down on by a snobby brewista for not saying "Venti"...hehe...so I took this story at face value and initially thought "No, that's not right, you shouldn't be able to loiter in a place of business, no matter who you are".
But, in reading the comment from your linked article, which states ""All the other white ppl are wondering why it’s never happened to us when we do the same thing.", I'm left thinking that if waiting around for friends is something that happens, and if there is a gap between how white people are treated and black people are treated in this location, then they should be on the hook for explaining why, or apologizing, which Starbucks has done.
Can any hardcore Starbucks fans comment on how the store they frequent handles this kind of scenario, where people are waiting for others to join them?