I don't really understand why you're comparing these two things? One is a group of people refraining from consumption of certain goods for personal reasons - health, ethics, climate impact, whatever. The other is a group of people consuming arguably more goods than they (we tbh) deserve since we're not willing or able to pay for it for one reason or another.
A better analogy would be comparing piracy to... I don't know, a veg-eater of whatever type who still enjoys the taste of bacon and resorts to stealing it because it's better to hurt the meat industry than to pay? It's a product that person really doesn't really need and absolutely would have never paid for, yet the person still wants it and obtains it in a way that hurts the industry.
(The analogy doesn't hold up since stealing physical goods has a different impact than distributing digital copies, but it's the best I've got off the cuff)
E: okay, after reading your other comments, I'm both confident this didn't address the point you wanted and confident I don't really understand your deal well enough to do so. Both of these groups have some members who have a problem with industry practices and others who are into their chosen lifestyle for other reasons. It seems like you've made some odd decisions about which groups are most prevalent among each and are framing your premise around that, and I don't think we're going to see eye-to-eye on it when the premise is Like This.
Or are you trying to say veganism should be more widely accepted because "DRM is wrong" is roughly equivalent to "animal suffering is wrong" re: "industry bad"?