Red Delicious and probably Golden Delicious, which have been around forever but have generally declined in popularity, are likely sweeter than any of Gala/Fuji/etc. varieties.
As another comment notes, Granny Smiths tend to be cooking apples for which they're very good.
Yeah, supermarkets have a disproportionate number of apple varieties compared to pretty much everything else. Might be a couple varieties of local corn but more likely at a farm stand than the supermarket. 3 major categories of potatoes plus small ones. Yeah, maybe 5 kinds of chilis. My farm stand does have more varieties of things like eggplant and squash.
As another comment notes, Granny Smiths tend to be cooking apples for which they're very good.