That's because Americans never had to prep in these modern times. The United States has the greatest transport infrastructure in the world and as we have seen with natural disasters like hurricanes, earthquakes, winter storms and whatnot, food and other necessities are rushed in. Private capitalist companies like WalMart, FedEx, Amazon, UPS, etc, have just incredible logistics to move stuff around.
Now I know that the dying MSM hypes up all of these events and gets people scared. Even today, when there is threat of a winter storm, the media goes into 24/7 frenzy and causes some folks to rush to the supermarkets in a panic. But nobody is going to starve. In fact, our biggest societal problem is obesity so many of us can well afford to miss a few meals. Not that that would happen, unless something like a comet hit the earth and killed us all. In which case, it wouldn't matter how much you prepped.