"On the 20th, this woman, Debbie, came through the drive-through while I was working," 20-year-old barista Andrew Robertson told ABC News.
"She was extremely pleasant, and we had some friendly conversation while her drinks were being made ... she had multiple drinks, and we didn't have drink carriers. I informed her and she was a touch frustrated like anyone would be."
Richardson said he also wasn't able to take the customer's trash because it would violate the California health code. Still, the barista said he didn't think Debbie was acting rude, and was surprised when she showed up the next day with $50 and a handwritten apology letter.
"Without the money, this was one of the most beautiful and heartfelt things I have ever read," Richardson said. "It absolutely made my day when I read it. The money was unnecessary. The card alone was the best part. I would have turned the money down had I opened it when she was there. It's hard to take things like that."
Angie Harris, the barista's manager, told ABC News how proud she was of the employee. "I think it was great. It's always good to see those customer connections ... we're really proud of him."