Art is an extremely general and subjective term. I have seen code that is artful. I have seen paintings that are artful. No artist can lay claim to what is art in a field they may be unfamiliar with.

I've seen code that's poetic and artful. Computer science, like any science, has artistic elements to it, especially when economy of motion is utilized.

Money isn't art. To quote Robert Graves: "If there's no money in poetry, neither is there poetry in money."

Creation of anything can be artistic. It can also be mundane.

Why should you feel that way?

I've never heard a businessman say "I'm disturbed that artists think they're engaged in a business."

There's nothing more noble about one profession or the other, every path has its place. It's not even worth getting into a discussion about "what is art" here (although I do believe that a creation that comes from your soul and expresses something about who you are and how you see the world to be art, no matter what your medium). Even if your definition of art doesn't include what someone else calls their art, there is no reason at all to be bothered by that. They're not taking anything away from what you do, so focus on loving what you make and don't worry about how others refer to themselves.

The Robert Redford film, A River Run Through It, has an interesting take on what a person can call their 'art.' Worth a watch.