It's an interesting perspective, I have to acknowledge. I'm viewing it from an extreme outside position (I literally kill and eat wild animals as a hobby), but an interesting comparison I can see might be to cannibalism. There's nothing practically wrong with making a facsimile human leg out of pork, calling it "I can't believe it's not human flesh", and selling it in a grocery store...but I mean, most people would find it distasteful and upsetting. They're not engaging in cannibalism of course, but the ritual of cannibalism, the idea of cannibalism, is unsettling in its own right to most people. If someone said "man, I wish I could eat people" unironically, I might not want to attend their next barbecue.

Your view seems perfectly consistent to me -- if you believe killing animals is morally equivalent to killing humans, then meat eating could be considered morally equivalent to cannibalism. Even fake human leg is still creepy to such a non-cannibal -- even fake turkey thus may be creepy to a vegan.

Perhaps it's because of the variety of reasons people are vegans -- many aren't truly abstaining from eating animal meat because they think it's wrong. Some are vegan for health reasons, or for environmental reasons, or because it's fashionable in their social tribe, or because they vaguely agree with anti-animal-eating philosophy but still internalize contradictory opinions. I know multiple adventurous vegans who would be ok eating roadkill deer if I served it to them (from their perspective, it does not contradict their belief that killing animals for meat is wrong -- it died in an accident, after all). But they would have a different opinion if I served them roadkill human, even if I showed them the human's death was purely accidental.