Most certainly not. However, if data suggests that men are more likely to buy a sustainable product when the packaging and slogan conveys a masculine message, it is perhaps something for these brands and communications to tailor their messages appropriately. 

I do believe that we should buy sustainably sourced products just because it is the right thing to do. I know that there are people from both genders share the same belief as me. And funnily enough, my mother is the one to call my father 'a numpty' for spending a bit more on a green product. For those that need that little push to help them decide - nothing wrong with making the product a bit more appealing. It's all for a good cause!