That graph is misleading at best, especially for the US.

If total consumer spending in the US is 50k and in Italy 20k, then it seems rather obvious to me that Americans are gonna spend a smaller fraction of that on food...

If you run the numbers, those two countries spend, in fact, almost the same dollar amount on food (3.2k vs 3.5k).

This is true but people will react negatively to this data regardless. The US does have this advantage, but you can also argue that the tradeoff is our food quality is much worse than other western countries.

This doesn't mean our food is cheaper. It could mean that we have other budget items that are larger than in other countries, such as healthcare costs. We almost spent more on childcare costs than countries further to the right in that graph.

Or the wealthier a nation is, the less political will exists to go after monopolies.