I understand your argument on gas. But I find the comment about tires to be curious. I literally will not buy tires anywhere else.

Costco:

- Often has a lower price on tires than other stores (particularly when they run a brand specific sale)

- Includes free installation

- Properly torques lug nuts/bolts

- Includes road hazard warranty

- Properly patches tires when you do have a service issue

Those are the highlights...