Could it be the WBT$ can no longer afford the CDs?
One key change is in the number of devices that don't even have optical drives to use a CD-ROM. Netbooks, tablets, mobile phones, smart TVs, etc.
CD/DVD ROM discs are amazingly cheap when purchased in bulk, cheaper than printing a book. With packaging, the cost of producing the CD-ROM library should be well under a dollar.
The data mining thing shoud be an enormous benefit to them for reasons already mentioned. Also, any webmaster knows where your visitors came from, or if the address was just typed in, the length of time individual visitors spend on the site, what you click on while there, and if they partner with some companies, can look at the 'tracking' or 'super' cookies on your PC and see some of your web browsing history.