Another element of the analogy:
Genres are flavor profiles, and like flavor profiles with food, we all have preferences and favorites. But even if we go back to the flavor profile over and over, there is still a lot of variation. A breakfast burrito is different than a street taco which is different than homemade empanadas. But they are all dungeon crawling (or whatever).
And, of course, fusion is a thing. You can throw fired jalapenos and asiago on a burger just as easily as you can insert a short dungeon crawl into a otherwise epic fantasy campaign.