David you don't have to replace your hens every year unless you are eating them of course. Most will lay for several years before they stop
I thought that too until I got some Salmon Faverolles. We had 14 birds and by the middle of the second laying year we were only getting 2 to 4 eggs a day. Fortunately we found someone who wanted them as pets. Otherwise, I'd have given them to someone who wanted them for people food or for dog food. I can't keep every chicken - we don't have that kind of room, or money. As long as the people getting them aren't going to use them as fighting bird bait or something gross like that it's okay if they use them for food.