> It's calorie-dense and high in sodium?

There's plenty of real food that is as heavy and as salted, and as such no healthier, than junk food. But it actually tastes good. (I can't exactly put the finger on what makes an Italian pizza better than a US 7/11 one, but it's not about the former being healthier).

I'd say it's the fermented, charred dough in combination with fresh, varied toppings.