Reference materials are much better suited to online or eBook distribution because they need to be updated to correct any errors or omissions, and to add new information as it comes up.
Actually, I find it's the other way around: Fiction I start at the start, and go through it page by page like everyone else. But searching through reference material requires the ability to flick through the pages, which can be easily done with a physical book. Sure, you might be able to search on an eReader, if your looking for a diagram you're kind of screwed.
Of course, most other regions like Europe or China don't consider the self-incrimination thing to be a problem at all.
I'm undoing moderation here but: Wrong. Even the eastern country where I live (Hungary) has provisions against self-incrimination. And public/private encryption is also legal. The only thing I can think of that isn't legal is encryption using your digital signature.
Top Ten Things Overheard At The ANSI C Draft Committee Meetings: (5) All right, who's the wiseguy who stuck this trigraph stuff in here?