I think that's because we'd then get attached to them and avoid selling them if they don't produce. I know that in a different game I had to sacrifice 50 chickens, so I named them 1, 2, 3... and so on, in part to keep track of where I was, and in part to not feel guilty of it. I did have two pampered and properly named show chickens.
It is, if you're is willing to pay Joja 500,000 G per percent that you need waivers for. You might need around 40 million for that, depending on how many stray percent you get from the goals you can complete partially.