Just being a smaller percentile of the population does not make one "marginalised". I'd hardly call vegetarians, as a group, marginal. There's nothing wrong with someone taking the piss out of you, or doing likewise. I agree most of it isn't funny, and (an example is quoted in the first post) a lot of it is just plain stupid. Something being stupid, though, or based on daft inaccuracies, doesn't make it offensive. It just makes the person doing the "fun-poking" look a little dumb.
I laughed the first time I heard "People Eating Tasty Animals" to be honest. Not the second time, some jokes lose their humour pretty fast, but to take offense at stupidity would mean you'd spend most of your life in a huff.
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