Unless you are buying Hindenberg brand tires, I doubt that they would be filled with hydrogen. Nitrogen inflation is reputed to have some advantages, but I surely wouldn’t pay extra for it.
While Costco provides nitrogen inflation at no extra charge with their tires, someone reported on this forum recently that his mechanic charged him…something on the order of $50. for the unsubstantiated benefit of inflating the tires with nitrogen.
Free? Sure
Extra charge? No thanks