Strawman; they logically are not “alive” in the same way humans are and cannot “feel pain” the same way humans do.
To eat meat, one must acknowledge that it means causing pain and suffering. If you're fine with that, go right ahead. But you cannot pretend there are no consequences. i say this, by the way, as an occasional meat eater. But at least I'm honest with myself and others...
My brain is not the same as yours. People who have live with 1 hemisphere are (likely) different than your brain (or however you want to define brain similarity). Your reasoning is not a sufficient bar to make an appeal to logic, on its own.
Currently, science has favored Jaak Panksepp (https://en.wikipedia.org/wiki/Jaak_Panksepp) above John B. Watson (https://en.wikipedia.org/wiki/John_B._Watson).