Contrary to anecdotes, most people in Europe are also pretty sedentary, don't cycle to work and don't do sport (there's probably more active people in Europe than US). We probably walk a bit more but there can't be that much in it.
So I'm still baffled at that difference.
For example, in Portugal a McDonald’s meal is about €12.
Meanwhile you can get a meal of fish or meat, mashed potatoes and some veggies plus Coke Zero in a glass bottle for €8.50.
Or a plate of rice, good quality salad (not a token one) and quarter chicken plus a coffee for €7.50.
Also... yeah we are pretty sedentary in Europe but it's another level in America. In many parts of US cities there are literally no pavements so you can't walk even if you wanted to. I can't think of anywhere in Europe like that.