Books shouldn't just be valued based on how much they cost to produce, but of the value of information inside and how much that information is worth to the target audience.
I think there's also a lot to be said in regards to how much value a reader has, too. As in, if there are more readers, will it make me, the author, more "rich" in other ways too (popularity, Twitter followers, etc.) so that when the next ebook comes along I already have thousands of people interested in buying my book that didn't exist before. A low price tag increases readers, which I think have huge individual values in themselves.
Now, if the book is extremely niche ... almost ridiculously so ... then a $3000 book probably would be okay, but in general I think this isn't going to happen too often.