As an American I have to giggle at a couple of these and then wonder what on earth the food you are eating over there tastes like since Taco Bell made this list not once, but quite a few times
Do you not have similar burgers? Are these foods not at all available or do you have to search for them (funfetti cake, Twinkies)
We don't have the chains of foods like you do in the US. We have some, but very few, compared to over there. But we don't have the population either. The whole population of this country (Australia) is about the same as just the population of LA.
We have McDonalds, KFC, Burger King (Hungry Jacks), Subway, Red Rooster, Krispy Kreme, Donut King, some pizza places. But we don't have these big chain restaurants like you have over there, Cheesecake Factory, Rainforest Cafe, IHop, Taco Bell, PF Changs, Bubba Gumps, Dennys, Johnny Rockets, the list goes on. So those things are a novelty for us as it's not something we can have every day if we wanted, we can only have it on vacation. These places have things not available over here and it's something different.
Portion sizes in the USA are HUGE and I think our food tends to be healthier and smaller portions. Sushi is a big fast food around where I live.
As for funfetti cake, I've never heard of that

Twinkies, haven't seen those either, but it's possible that somewhere like USA foods may import them and sell through their website, but we don't have them available here generally.
We do have things that are not widely available in the US though, Meat Pies, Sausage Rolls, Vegemite, Cherry Ripes, Tim Tams, some great beers and wines, to name a few.
Its not just the USA though, that's part of the fun travelling, is having different foods that you don't normally get at home. My favourite place for different food is Switzerland, I love the Swiss food.