In that case, you shouldn't expect this information for free.
If you want free stuff, you should be okay being advertised to.
If you want free stuff, you should be okay being advertised to.
"Pay $1 to access this file" OR Sign up for email sends confusing signals to users. To the author, book is not worth $1, it is worth one email list signup. To the user, the book's value is entirely relative. They can offer up their email (positive value perception), or they can leave the site (zero value perception).