I believe animals can "experience being killed" and justify my eating of them mostly by the fact that eating them increases my productivity which helps me work more optimally towards reducing the suffering of other sentient beings. Also, I am somewhat selfish.

Is that even disputed, that animals can "experience being killed"? I don't doubt there are sentient animals, other than humans. For example dogs, crows, dolphins, elephants, probably tons of other. Once animal can predict future and react to it, he can't help but be sentient - otherwise how could he know what part of the future he can change, and what part is the einvironment.

Killing them to eat is IMHO justified by the same reason tiger has the right to kill his prey. We're predators (ok, omnivores, but still - we eat meat).

Animals can not only experience being killed, there are documented cases where intelligent animals like orcas and dolphins have made and carried out a decision to commit suicide.

Humans in general even justify the killing of humans in special situations, who obviously are capable of experiencing being killed. It's eating the remains that's repulsive in the case of more intelligent species like humans, dolphins or dogs, isn't it?