The mainland is an entirely different story and the gas prices there are 9.28bz or 4.64usd for regular, not that different in price but lots of highway and plenty of places to drive long distances.
also public transportation in the form of bus. several choices of quality bus, from ride with the Mama, Paw and the chickens to express with air.

White Sands Dive Shop
https://whitesandsdiveshop.com/