I have had cravings for meat too when I'm pregnant and/or breastfeeding. I liked the smell of stew when I went over to my parents' house. Sometimes I even dreamed about it.
However, I still always say no for two reasons:
1. I believe that it is wrong to take away another creature's agency. It is wrong to control another being's choice of where to live, when to have babies, what to eat. In my opinion, it is wrong to force another animal to have babies and to take away the babies after they are born. I think it is wrong to "harvest" another creature when it is time to eat it with no fair hunt or fight.
2. The whole idea that somehow "grassfed" cows and freerange chickens are environmentally sound options for meat eaters is incorrect.
Unless you live somewhere grass grows year round, cows are not grassfed in the winter. They are fed alfalfa and dried grass which must be raised in fields during the summer. This uses a HUGE amount of water. In my backyard, a big river flows during the months when alfalfa can't grow. When the alfalfa fields are being irrigated in the summer and fall, the river completely dries up, taking with it lots of wildlife - frogs, fish, insects, birds...
Additionally, the grassfed cows wreak havoc on the water supply. They both consume large amounts of this scarce resource and they pollute it with their bodily wastes. I like to take my kids swimming in the little streams in the mountains near our house during the summer. It is very hard to find one that is not clogged and stinking of manure from these creatures. They compact the ground with their hooves. Plants cannot grow where there are many cows. It's sad to see what once must have been beautiful meadows on public land, now made into manure soaked, compacted ground.
Freerange chickens may be a little better environmentally than the cows; they use less water and food. However, like farmed salmon, they can pass diseases to thier wild cousins. They also can act as a vector for wild bird diseases that are then passed to humans. Flocks of chickens need to be carefully managed to avoid these problems. The example of a freerange chicken flock I have witnessed consisted of closely packed, stressed birds living in not so clean conditions. They were very close to ducks who were in contact with other wild waterfowl. Poor plan, I think.
Anyway, that's why I don't eat farmed meat. I don't eat other meat just because I don't need to. When I have a craving for meat I just remind myself that it's healthier not to eat it anyway.