I'm operating on an iPhone right now, and can look up that breeders contract, but I can't imagine how they can enforce food selection. Do they expect puppy buyers to keep receipts? I highly doubt many of those things ever get enforced. The examples you gave might get you off the hook for any guarantees, but I've seen some odd things in breeder's contracts. I completely understand why you would put them in there. The puppy buyer is more likely to follow that course of action if you've had the conversation with them. I haven't read your contract, so I'm not referring to yours.
By the way, I enjoyed those articles that you linked.
What contracts do (or should I say, are supposed to do) is spell out the conditions and expectations of both parties to cover any warranty/guarantee. We can use any 'product' as an example for contractual warranties/guarantees, for example a Computer. Most are covered under an extended 'contract' with the manufacturer, but become null and void if for example the purchaser decides to open the computer and switch wires around etc. The manufacturer can not say 'Give me the computer back', but they can say, 'Sorry you are out of luck, the repair is not going to be covered and you will have to pay for it to be fixed'.
But you are right! There are many breeders that feel a contract is a dictation, and some of the things included would never stand up in court (but some will, depending on the judge).
I have 1 supplement that I require all puppies be put on for, minimum, the first 24 months of life (I do not spell out where to get it, I will supply where I get it if asked), receipts are required to be kept, can I force a purchaser to do this, no I can't, but any issues that may arrise from not giving it, are also no longer my responsibility.
I, personally, am a stickler for contracts. When I have purchased a dog I follow them to a T, if there was something I didn't agree with I would discuss with the breeder or not purchase the dog.
Thanks for the compliment on the articles ;-) I have to get back in the swing of updating the blog...maybe I'll put my thoughts on contracts down on paper