I highly doubt that lending a book forever for one fee makes much of a difference to the company's bottom line. If a book is that popular, the library will buy multiple copies anyway simply to satisfy the demand created by their patrons. If a book isn't that popular, it would never wear out anyway.

I would also suggest that $2 for 2 weeks would put libraries out of business. Indeed, it is placing an undue burden upon them because the resale value of books is often under $2. (But hey, publishers can do that since ebooks effectively abolish the doctrine of first sale.)