Much of the blame for this has been attributed to Wikipedia and there is one simple reason.
To quote the classics,
...though it has many omissions and contains much that is apocryphal, or at least wildly inaccurate, it scores over the older, more pedestrian work in two important respects.
First, it is slightly cheaper...
All it needs is the words Don't Panic printed in large friendly letters.
Wikipedia is now officially the Hitch Hikers Guide to the Galaxy.