I think bands like Crass, Youth of Today etc has brought it in to the punk scene. I would say it's more of a political thing, Crass was a very political band, and Youth of Today's song "No More" is about the animal rights message and not the health issues…
Check out the documentary The Punk Years, which mentions this in one episode:
Programme 5: A Riot Of Your Own
An outraged cry against the rising right wing sentiment in the country and a counter to National Front marches, organisations like the Anti Nazi League and Rock Against Racism formed. The band leading the way in energising punk in a political sense was The Clash, who played an integral role in the Rock Against Racism movement (as did many other punk groups), taking the stage alongside groups like Aswad and further cementing the links between punk and reggae. Anarcho-punk bands like Crass also began to emerge, taking on board anti-nuclear and vegetarian causes in opposition to the right wing politics of Oi! Bands. We discuss the political confusion caused by the mass of ideas thrown into the air by punk.