She's not wrong. It's why. It's also why I tend not to eat even the "happiest" lamb or mutton (actually that's because of sheep burps). Last time I had red meat, then, was Easter dinner. We bought a leg of lamb, organic and locally sourced, from our local butcher. It was melty. And I tried not to feel guilty.
So generally I avoid beef no matter what. In their book The Way We Eat, Peter Singer and Jim Mason do an excellent job of pitting the various ethical factors in our dietary decisions against one another. In terms of beef, they convincingly argue that pasture-fed organic "free range" cows are actually more damaging to the environment than factory-farmed ones fed corn and other grain because eating grass makes the happy cows fart more. This produces more methane, which is a greenhouse gas 90x more potent than CO2, and accounts for the fact that by some estimates, our North American meat industry alone is responsible for around 40% of our total greenhouse gas emissions. Ugh. Which means that even if I get happy beef that has been shot in the back of the head while watching the perfect sun set with its adoring bovine family, it's still going to be responsible for record-breaking temperatures, droughts, water shortages, etc. for something like the next 800 generations of my offspring (apparently greenhouse gases stick around for about 20,000 years).
But ho, what news? Apparently, we're working on the scientific equivalent of bovine bean-o. See here in the March 2011 edition of Business Green!
So maybe, just maybe, one day I'll be able to eat a non-lentil, non-tofu, non-mushroom burger again. A boy can dream.