That's true, but you have to spend some time going to buy the ingredients, spend some time preparing the meal, and spend some time cleaning up afterward. It sounds like it's just too inconvenient for these folks to go to all that trouble.
I suppose I shouldn't suggest paper plates should I?
Really it is sad, it takes very little time to sit down and work out quick and healthy meals. By the time you add in the "Sitting in the drive thru" time you would probably spend less time shopping, cooking and cleaning up. Not to mention all the money you save.