GP spent a month in SF so I assumed they weren't a tourist. They also mentioned organic groceries so they included cooked meals in this. Even if you eat out, you won't have to pay $40 for a healthy meal. You can get something good for $15-20, which is still pretty expensive... but not $40, and not significantly more expensive than comparable unhealthy foods; of course McDonalds is cheaper, but then again unless we're talking about people that have no money to spare, it's more likely they're choosing unhealthy food rather than being forced to buy it.

It's really easy to avoid sugars and when not in SF its even cheaper. In Ohio a healthy meal for 2 would be ~$5. $0.50 for rice, $0.50 for beans, 2 peppers for $1.50, pound of chicken for $1.50.