I'm not going to drive my co-worker to lunch every time
Why don't you want to drive them?
He always asks me every time to bring him to lunch and I'm tired of it
It is understandable to be tired of helping him out. One day he might be able to help you back. Have you told him how you feel?
I don't care, he's a prick.
If it keeps bothering you you need to tell them no and that you feel used. I think he might realize how one sided your relationship might be at that point.