I agree. They are worth keeping just for fertility. Everything else can be viewed as a bonus. 

I raised a batch of 20 freedom rangers for meat 2 years ago. I did free range and will not do that again. I now have 8 laying hens. I'm pretty new to this. I'm using deep bedding to produce compost. Every couple days I add carbon and biochar then feed them on top of this. Seems to be working well.