But this is not a huge factor in the real world when it comes to the meat industry. Cat food is not nearly its main driver.

So it’s just a matter of degree? Meat could be a delicacy for humans as long as we weren’t overconsuming?

I think it would be ethical on the part of the aliens to strive towards a solution for their diet that doesn’t involve killing or harming sentient beings

If they’re obligate carnivores, what could they eat instead, if killing any living creature for food is morally equivalent?