I think the original article saying fruits/veggies cost $18.16/1000 calories is definitely bloated. I wonder what they were buying for that. If you calculate that out to 2 people eating 1500 calories/day, that is $1600/month in groceries. During the summer when I was eating a lot of fresh fruits/veggies, I was reading up about raw foods and reading how much people spent when they were eating mostly fruits/veggies (and some other stuff like nuts). Although the cost seemed slightly elevated, it certainly wasn't that elevated.
You can't out-exercise poor eating habits.