There is a lot of desertification of farmland going on, including in the USA.

It gets abstracted away for richer countries as they can outbid the poorer countries for food. In developed economies, most of a particular piece of food's price is not the costs that go to the farmer, but costs that come later in the process, so that cost increasing is also felt less.

Heatwaves on the other hand affect the western countries directly.