From “William Caxton“, at The Science Show:
More than 500 years later a copy of Caxton’s first edition of Chaucer became the most expensive book ever sold, knocked down at auction in the 1990s for 4.6 million pounds. But in the 15th Century, the obvious appeal of the newly printed books lay in their value for money. Books became so commonplace indeed, that some snobs employed scribes to copy Caxton’s printed editions back into manuscript, while both church and government became alarmed at the access to new ideas that the printing press offered to a widening public. [Emphasis added]