More than 25,000 Brits have signed a petition calling for a ban on leaving fridges open.
It comes as a new study finds open-air fridges in supermarkets and other retail outlets use about 1 percent of the UK's total electricity.
"It's a terrible waste of money and some stores have introduced closing doors," Labour MP Mary Creagh told The Telegraph.
The man who started the petition, Jonathan Golding, told the Daily Mail he was at a restaurant and had just been given a plastic knife and fork when he came up with the idea.
"I was in an environmentally conscious mood. In the corner of my eye I saw a fridge and it was open, and I just thought that couldn’t be very environmentally friendly. I started researching it and it kind of went from there."
His sister Gem has joined in.
"You wouldn't leave the fridge open at home, so why are there about a gillion's worth of them surrounding us in the supermarket?" she asked in a Facebook post that went viral.
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The study, carried out with support from the UK's Department for Environment, Food and Rural Affairs, found retail food outlets are responsible for about 3 percent of the country's total electricity consumption, and between 30 and 60 percent of that is refrigeration.
"From next April all companies of a certain size have to declare their greenhouse gas footprint, so this should spur them into measuring their gas bills and trying to work out ways to reduce them," Creagh told The Telegraph.
Gem said on Monday the response to her brother's petition has been "crazy".
"To all those who have sworn at me and called me an idiot, sorry for clogging up your newsfeed again," she wrote, posting an image of the Daily Mail's newspaper article on her efforts.
If the petition reaches 100,000 signatures, it'll be considered for debate in the UK parliament.