Tall Milk no Coffee

I was craving a hot chocolate after my salad so I walked in the freezing rain (yes freezing rain) to Starbucks. I order my grande hot chocolate with "whip" and waited over by the barista. That's when the magic happened...

This wet woman (she had no umbrella) in a wool coat comes in and asks one of the barista for a cup. He looks at her for a moment hands her a "tall" one. She processed to the the exit station that's filled with cream, skim or regular milk coolers. She takes one and fills it up. I'm not sure which one she took because I wanted to be discreet. On top of that she goes back to the barista and without asking puts her wet mits on lids looking for that one that will fit her tall cup of milk. The barista rushes over and gets the correct top for her. She rushes over to the exit station, puts it on the cup and exits, with no umbrella. By this time it's raining harder than it was earlier! What is her story?

Nope, she paid for nothing. I didn't know Starbucks was giving away free milk.