Yes.
For as long as I can remember a new Mac has come with Contacts, and before that Address Book, with one card in it to get you started. The telephone number is for the free telephone support you get with a new Mac. It would have been quite useful in the days when most people didn't have an internet connection.
If you don't want it, select it and hit the delete-key. I'm sure Tim Cook won't be offended.
C.