Is it not the intent? A farmer generally isn’t going to raise an animal for fun. That wouldn’t be profitable, and small farms are already difficult to make a living on.
I can entertain the idea that I could walk up to a farmer and ask them what their intent is, and they reply, “why it’s to extract nutrition from land that is otherwise unproductive, of course!”. But the end result is the same in either case regardless of stated intent: animals are being killed unnecessarily.
To be clear, none of this applies to people who rely on animal products to survive (e.g. people in the unproductive land you mentioned). I’m talking about people like myself (and likely many others here) who have access to supermarkets and other products of a globalized food system. Like Uncle Ben said, with great power privilege comes great responsibility.