hmm I've known three people who I'm fairly sure of their type that are vegetarians or vegans.
Ones an EIE, has been a vegan since she learned about where meat and animal bi-products came from. She is passionate about animals and has been volunteering for the SPCA since highschool.
A probable SLI who gave up meat, but eats fish, when making a radical healthy lifestyle change. She did a lot of research on how the slaughter industry works and the effects of meat on the body; she'll often quote facts about it and such.
An IEI who was raised by vegetarian parents, he isn't as passionate about the ethics of eating meat as they are but still doesn't think it's right
I have no idea if this is consistent with type, but the two NF's are more concerned about the ethics involved whereas the ST looks at it from a more personal logical point of view