I'm thinking their hotdogs are huge, like 1/2 lb?

And the slices are huge also.

And most people probably get a 32oz cup of sugar water with them.

Maybe I'm overestimating.

Fair, I did leave out the soda that comes with the hotdog. But that could be a diet soda. (and seems to frequently be, given that my local Costco has 4 diet coke spouts, as opposed to 1-2 of any others)

I did look up the calorie count for both. 550-ish for the hotdog, 650-ish for the pizza.

The hot dogs are 1/4 lb, with the bun it's probably 500-600 calories.