I'd hate walking everywhere, having to get tiny amounts of groceries every day instead of stocking up every 2 weeks, etc. Walking/standing all day at conventions feels like death and a half a mile trip to the fast food places around here turns from 2 minutes to 10 minutes if I walk, which I tried when someone from Europe said that's walking distance. Walking such distances just makes me constantly wish I was driving…
A lot of it comes down to how the cities and grocery stores are designed.
In the US you drive to a shopping mall, navigate through a sea of parking, walk maybe 1000ft of aisles, then spend 5 minutes in the checkout process waiting, scanning, bagging, and paying.
In the European cities I've lived in and visited, mixed zoning means you're likely to have a supermarket near your house or work so doesn't take any extra time to travel to, there's no parking so you just walk in of the street, the stores are about the size of a 7-Eleven so it's fast to find what you want, then the whole checkout process is crazy efficient.