My local bar is tended by a software engineer. It's only open on Saturday evening cause he does it besides his day job.
But it's great cause he does it for the love of mixing cocktails, and introducing people to great drinks from all around the world.

And he obviously doesn't really need the money, cause when you show an interest, most drinks are on the house.
He uses a pencil, paper and a mechanical calculator to tally up the bill, which I absolutely understand when your career is in IT.