First to answer your question: As pagansoul said, they want you to buy both. Also, I think that they don't REALLY care about the kindle version or they would price it appropriately.
BUT, to respond to your issue...
I have not purchased a technical book in the last 5 years. Why would I when its going to stale by the time I read it? It takes months to write, edit, print and distribute a book. BUT, I can go online and find what I need from an expert and the answer is based on TODAYs technology, not last years. So I guess that I don't mind that technical books suck on the kindle.
