"Lying bad" is such a numbskull take

Deontology is the ethical basis for veganism. If you’re lying to your meat-preferring friends to trick them into eating plant-based alternatives then you’re using your friends in an attempt to further your own aims; you’re using other people as a means to an end. That’s not a mildly bad thing, that’s a violation of one of the ethical principles (prohibition on exploitation) of veganism.

Now I don’t support reacting with violence to something like that but I do believe it’s fully justified to decline to dine with a friend/relative in future who does that.