Thanks for writing us about this. As the publisher of these books, we sell at the list price, and Amazon discounts from that price. If we lowered the price, Amazon would discount from that lower price.
We do have some discounts that you can take advantage of to get a cheaper price on oreilly.com.
If you're buying more than one ebook, use discount code MBBGS to buy one ebook, get one ebook free. Details are on https://members.oreilly.com/account/benefits.
For print books, you can use code OPC10 to buy two books, get the third free. Details are at http://shop.oreilly.com/category/customer-service/b2g1f.do.
I hope these discounts help, and we're happy if you buy the book direct from us or from another retailer.