Interesting idea. I'd definitely want this for Minecraft and unlike most posts, it's "Minecrafty". Just one question. What if you break the back yard of the butcher's house? Will he still breed and spawn animals or just stop?
I feel like these things would make villagers too complicated and I couldn't see a villager killing anything, especially since they can't hold items or attack. This may not be a stereotypical building villagers suggestion but I'm not a fan.
As the villagers will not be boring to players of this is added. Instead of going around doing nothing, they should have jobs for themselves for their livelihood. Becauss of this, the player feels that he will buy the items from them.