[msluyter]

Adding to the varieties of other explanations countering your "one explanation:"

1.) Time. Although I'm (perhaps overly) sensitive to which foods are healthy and which aren't, I often find myself eating sub-optimally simply because I can't muster the time/energy to make something healthy, do the resulting dishes, etc... And veggies can be some of the most labor intensive. Or, you want a quick snack that's also really healthy? Here's $5 for a small bag of kale chips (see "Cost," below.)

2.) Skill. It's taken me a while to learn to cook well enough that much of what I make is at least on par with (non-gourmet) restaurant food.

3.) Cost. Compare the beans with sugar to higher end -- organic, in particular -- varieties.