Term of endearment or abuse? TBH it always makes me smile when I get called a yoghurt weaver, even if it wasn't meant nicely, but know some crystal types who takes offence at the term.
Sorry this is the first time I've heard it. The derogatory term I remember from my youth was "Granola". As in "Look at the tree hugging Granola over there." I think this may be a shortened version of "Granola Chomper". I latched onto the term "Granola Bar" for health food restaurants, Juice Stands and the like. Stay Brown, Rev J
Think it comes from more right on activist types who disparagingly talk about folk who rather meditate on the problem...it's going to be as much use a weaving yoghurt. I'd be interested to hear other explanations though.