I keep thinking that I know plenty of people who would sign up to be guinea pigs as long as they were representing their own pet WOE, “ethical” or not. I mean, if someone said to me hey, I’ll give you $ and I’ll provide you with all the organic pastured-animal fat you need for the next six months (or six years) as long as you limit yourself to this fat only and keep a food diary, I’d be signing up tomorrow.
(And I’m guessing if you gave the same deal to a vegan, substituting olive oil or even soybean oil, they’d be delighted too.)