10 percent now claim they think about carbon footprint when buying food. While that doesn't sound like much, especially when 80 percent of Europeans are happy to ban both DNA and Dihydrogen Monoxide in food, it is quite a lot. So much so that if you believe it I have a bridge in Amsterdam I'd like you to buy.
On surveys you can find 10 percent of people agreeing to almost anything that doesn't sound terrible, like dog fighting. That doesn't mean they do it, it means they want others to think they do it.