Have you ever met a bartender who didn't seem to want to engage any customers and seemed mildly irritated any time you asked for something? Of course staying confident and friendly with customers at all times can be challenging, but it is the nature of the beast. You are on ALL the time. Assure the interviewer that you have an interest in the customers.
"I'm outgoing and love meeting new people. Whether I'm at work or out with friends, I enjoy making conversation and getting to know others. Everyone has a story and I think it's fun to ask questions and listen. You never know how interesting people can be!"
Entry Level answer example
"I am a naturally social person. My customers love to talk to me, and they appreciate the ear as well."
Experienced answer example
"I care about my customers and show this by listening and actively participating in a conversation with them. I'm authentic and have great people skills."