Some portion of the other 70% is going toward legal fees to protect "their" intellectual property, developing new ways to monetize the windfall, lobbying to obstruct copyright reform, running lower-margin businesses unrelated to academic publishing, and so on.
40% profit margins now, not 30%, but I completely agree: it's critical to keep an eye on what the company is actually doing rather than sweeping it under the skirt of the economic term "value," which never ceases to amaze in its ability to diverge from the more common definition of the word.
