If on a trip, I would not leave the fastest route to go to one, but if it were on the highway I was on, I would definitely try to plan a stop there...mostly because the bathrooms are so amazingly clean. How many other "gas stations" can you look at art on the way into and out of the bathroom, and then buy one of the art pieces if you want.
Even with 120 gas pumps, the closest one to me is often full. Not sure how they keep enough gas on hand to service all their customers.