Some are vegan for health reasons
Then, they still wouldn't want to eat meat (as ignorant as that is).
And, as we all know, processed food (and that's what this is) is always better than natural. *rolls eyes*
Some are vegan for the environment
It's still not clear that laboratories manufacturing "meat" on a large scale would be any better for the environment. The labs may claim it is, but that does not make it so.
Most are vegan because they are against killing animals that feel pain
Not just killing -- harming. Tell me, where did the seed tissue for growing this "meat" come from? Some animal had to be harmed along the way to enable this manufacturing process.