There's a link between using reusable shopping bags and buying junk food.
Really. Researchers from Harvard and Duke did the research. They say it's a classic case of consumers feeling like they earned the opportunity to indulge in something unhealthy because they did something they felt was environmentally friendly.
Kind of like getting a salad for lunch, and then adding the extra large fries and Big Gulp.
Uma Karmarkar, an assistant professor of marketing at Harvard Business School, explained the phenomena to the Harvard Business Review:
"You give yourself a cookie. In this case literally. In consumer psychology the word 'licensing' is the key. If I behave well in one situation, I give myself license to misbehave in another, unrelated situation," she said.
"In this case bringing a bag makes you think you're environmentally friendly, so you get some ice cream. You feel you've earned it."
I've seen a lot of arguments on both sides of the plastic bag debate — some of it compelling, some of it ridiculous. I don't think this research is going to change anyone's mind.
Unless you're in the junk food business. Will we see makers of chocolate chip cookies and Twinkies line up in favor of plastic bag bans? I'll be watching!