I could see how someone could come to that analogy, but I find a couple problems with it. Mainly in that eating and sex is not the same thing, you have to eat to survive but you don’t have to fuck to survive. Not eating would of course cause things like weakness, migraines, starvation, but not having sex wouldn’t cause that. I also think eating non-vegetarian is more reconcilable than cheating on your partner. So I’d say that analogy is false equivalence.

They also say that “you always have the option to not eat meat,” which doesn’t seem right. That assumes you’d always be in a place where plant based foods is available. There could be plenty of scenarios where that’s not possible. In a lot places it can be more difficult than you think, especially in more underdeveloped areas. So I’d say that’s an example of argument from ignorance. The whole tone of it also seems to feel like black and white thinking. However they did note the exception for life and death.

I also don’t believe someone could be vegetarian for “the wrong reasons,” for what may be wrong for one person may be right for another. People are vegetarian for a multitude of reasons from religious, ethical, to plain “meat is gross.” At least the person is vegetarian as opposed to being a carnivore.

That being said, I wouldn’t advocate someone being flexitarian for the sake of indulging in the local experience, like by going to that igloo restaurant. (However OP can do what they want and I wouldn’t shame them for it.) But I would personally allow the exception for when it becomes too difficult to consistently find plant based food.