Me not eating meat changes nothing. If I wanted to make a difference I'd go campaign, buy a domain name and set up some website and make people aware etc.
The truth of it is, I do care, deeply, I have had pets all my life, who have been healthy and happy by the kind way I've trained and treated them. But I don't have time to go to the government and picket for them to do the right thing. They should already be doing something about it all. I as a single person am powerless. Not eating meat, given the trivial amount I consume, would do nothing.
And if you say "but if everyone thought that way" you'd be absolutely correct, if 70% stopped eating meat unless humane practice was everywhere, then it would make a difference. But that will never happen in this world now, too many people don't care, don't think about it, waste meat and throw it away, are too busy to think about it with 3 kids a job and school runs, etc etc.
Not eating meat is not the answer without so many people doing it as a campaign, and it just won't happen. So not eating meat is not the answer to animal cruelty I'm afraid.