I am a newbie and had to buy layer crumbles today. I was stuck between a feed that offered animals fats and animal protein as incredients. Another feed was FREE of these two ingredients. My question is what is the difference and why would I want or not want these two ingredients? Is the AF/AP free feed pretty much just designed for those wanting a "natural" feed and not really beneficial in any other way? Would love to know, because the latter feed is twice the price!!