I spent most of the last 15 years in Italy, where people care about their food. They care a lot, and will absolutely discriminate between various tomatoes based on where they're grown, different kinds of pasta, and many other things to boot.
In the US, I think we tend to just look at the price and mostly go by that if the product is not clearly awful.
It is changing though: it's possible to get real Italian Parmigiano cheese at the Costco here in Bend, Oregon. Growing up, all I knew of "parmesan cheese" was that green crap that comes in a can, where they were apparently using wood pulp to bulk it up.
EDIT: BTW, this book by Tyler Cowen has some interesting stuff about "why food in the US was so bad": http://amzn.to/2dNxksx
I find higher quality food to be a case of rapidly diminishing returns. When I'm cooking for myself, occasionally I'll take the time to make everything from scratch with fresh ingredients and it will be nicer, but it's only 10-20% nicer (if that can be quantified) for several times more effort.
I think each person values the increase in food quality differently. You could rate the difference between a store-bought packaged croissant and a freshly baked French croissant at 10-20%. I may say that the French one is 95% better, as the a store bought one is inedible for me.
Neither one of us is inherently right or wrong. It's a matter of personal opinion, and even though we try to, it is not really possible to quantify the difference as a percentage in any meaningful way.
I think the discussion here is trying to highlight that many people in the US value better food less than many people in some countries on the old continent. For a given choice, an American will not think that the difference is worth the price (or effort) while a Frenchman or an Italian (I'm trying to use example s from this thread) will not even consider eating the lesser version.
I speak from personal experience. I've spent most of my life in the US and six years ago moved to Europe. My tastes have changed, and whereas before I like American food, now my tastes have shifted and a lot of American food does not taste good to me. Now, when I go to the US, a lot of food is at best flavorless and at worst disgusting. Most glaring examples are breads, cold cuts (a.k.a sandwich meats) and tomatoes.
BTW, this is not universal across all foods. I still find American hamburgers (not fast food) to be better than their European alternatives.
I'm not sure I'd limit it to 10-20%, there are some classes of things that are hugely different... I find that making my own stock/broth is at least twice or three times as good as pre-prepared, and even among pre-prepared there's a huge variation. This becomes much more pronounced when used as a sauce base.
I find some things I don't notice as much difference (cream, butter) as I will others (milk, eggs)... There are other things that are a matter of taste (grain, grass, grass-finished beef). I wish, for that matter, that more labels contained what they were fed especially for milk and eggs, as the difference between brands/containers and locations is huge.
I try to cook at least once a week, and sometimes that means spending a day making broth/stock (mushroom is an absolute fav, but the most expensive where I live). I find that there are just a few things that make a huge difference, and others not as much... others still are a matter of preference. I also find that mouth feel is as personal as anything else in terms of enjoying a particular food.
The idea that the Mafia defraud themselves is quite funny and those endless movies/tv kitchen scenes would be funnier for it, "don't burn the sauce and use the real oil".
