Now you've met one.
That's a ridiculous generalisation; it totally depends why they're vegetarian.
Yeah, if it's the taste or the concept of eating meat, they're not going to want a substitute.
But if it's animal cruelty or environmental concerns, those are ameliorated by even lab-grown meats, nevermind the plant-based taste-alikes.
It's dangerous to make blanket statements about what all vegetarians think. For example, on the question of why someone has chosen to be a vegetarian, I've heard a long list of different reasons, including: animal welfare, environment, their own health/longevity/energy, not liking the taste of meat, not enjoying the idea of eating an animal's flesh (even if it were ethical), their religion encourages it, and/or it's their default because they were brought up that way and have never tasted meat.
Vegetarians do not want to replace meat. (I mean, they are already vegetarian). Anecdotally, I haven't met a single vegetarian/vegan who is interested in Impossible or Beyond Meat substitutes. Such products are instead very helpful for those who want to reduce read meat in their diet.