Very well said, Sean.
We can make a personal choice with regard to which yarn we use; and if one is so inclined, can join the groups that are trying to change the practice. Thousands of sheep on a farm are hard to keep track of and inspect on a daily basis; millions of chickens are hard to manage if allowed to roam free; if pigs get out, they just keep going. Farming on these levels is a business and the animals are their commodities, regardless of how we view them.
There are many practices in farming and meat production that are objectionable. Having us argue about them here doesn’t change them in any way, but there are organizations out there trying to change the wool, poultry, pork and beef industries to be more humane, and I’m sure would take all the help they can get. Boycotting certain things is a way to feel that one, personally, is not contributing to the practices that are objectionable.