A good thought exercise is this: would it be equally valid to say that a producer has no claim against someone making thousands of copies of a digital good and selling them for $1 a piece ? If the answer is no, then what makes the fact that they are giving away the copies any different ? In both instances, the producer has had their right to determine the terms of the sale arbitrarily removed without their consent.
In no other areas of our economies do we allow such nonsense to go on. You can't walk into a retail store, fill your cart with items, and then dictate to the cashier that you'll be paying 10 cents on the dollar for the items and walk out of the store. If you don't agree with the terms of the sale, then you find another producer that has more favorable terms or you go without. If you want/need the product that bad, then you'll agree to the terms of the sale. It's that simple.
Edit: and yes, I understand that the linked article was about the cost attributed to such copies. It is correct to posit that not all copies equal valid lost sales. The problem with this type of argument is that it is often put forward by those that also promote the idea that sharing of copyrighted digital goods is a consumer's right because such goods are "information", and not a tangible good. It's a ridiculous stance to take because it completely hand-waves away the actual time and money that went into producing the "information".