Reducing pain and suffering is better than not doing anything at all, and it's childish to assume that we can do anything more than regulate our food habits, and perhaps a couple of those around us. I'm vegan; I'm not deluded enough to think that my eating habits are anywhere near mainstream. There doesn't seem to be any end in sight for animal agriculture, whatever my personal feelings may be about that, so the next best thing one can do is reduce suffering where possible, and in-ovo sexing in hatcheries works a small way towards that.