Assume everything is on video. In today's world of ubiquitous, miniature cameras, it probably is. Your customer service problem becomes 100 times worse when it's broadcast for the world to see.
Make the problem go away as quickly as possible. How much does a bag of donuts really cost Dunkin' Donuts? Compare that to how much the world seeing a fiery incident where an employee yelled at or got physical with a customer would cost.
For online complaints, advice varies. There are two camps on how to deal with angry customers on the web. One says to respond, make things right by offering freebies, and eventually asking the customer to remove their negative remarks. The other says to ignore: Responding only increases the SEO value of whatever page on which they're complaining. In general: Respond when possible, but don't feed the trolls.
For its part, Dunkin' Donuts has not addressed the incident formally, but the company has noted on Twitter that the franchise owner plans to recognize Adar for his actions.
That said, as a final tip, if you're going to have a corporate Twitter account, go ahead and use your grown-up words instead of subbing in "b" for "be" and "4" for "four."
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