So on a recent trip to Mexico, I was riding with a friend who had to make a quick stop for some gas. All in all, this really wasn't a big deal. It's certainly nothing to get excited over.
However, there was one huge difference about buying gas in Mexico - they pump it for you.
The attendant will ask you what kind of gas you want, how much, and take care of everything else. If I remember correctly, there are two types of gas you can buy, regular and premium, but don't quote me on that. Green is regular (I think) and red is premium. You ask for either el verde or la roja. By the way, a gas station in Mexico is called a gasolinera.
Yes, good old-fashioned full service gas stations are alive and well in Mexico. Imagine that, not having to get out of your car, and it doesn't even cost you extra. Wow, real customer service. Something I'm certainly not accustomed to here in the US