That is such a sad sorry misunderstanding of karma.
Then every species that eats other animals is evil? Just about the whole planet is evil then and pretty much the entire human race over all of history. Even certain plants that eat insects are evil.
It reminds me of when my teachers told me when I was a child that anyone that didn't believe in Jesus Christ and doesn't get baptized goes to hell and I asked her if Buddha was in hell then because he could never have even heard of Jesus and she said yes. (I did a little paper on Buddhism in grammar school).
If Buddha is in hell then I wanted to go meet him there - cuz that dude was really cool and I was even more interested in him than JC because he could teach me how to be enlightened - even though I appreciated JC taking all my sins and all - it wasn't nearly as interesting.

If most of the planet and pretty much all of nature is evil, then ok - I'm evil. If cats, dogs, bears and even chickens are evil - then at least I'm in good company.
We can have a really great time in hell together all of us, partying with Buddha!

Oh - and yeah - secret lives of plants rocks! I used to have that argument with vegans on gitmr all the time. I can "hear" plants and know that they experience pain but I eat them anyway. They would tell me that plants didn't hurt so much because of their undeveloped nervous systems. Hmf. Tell that to the plants! Just because you can't hear something scream doesn't mean that it doesn't.
It's not just vegans and certainly not all vegans can't think - I never said such silly things when I was a vegan. People don't think well all over the place and can act out their bizarre imbalances through all sorts of belief systems.