I can't go into BMV at Brunswick and Bloor and not buy something. Even when I'm just killing time or browsing, I leave with tons of books.
There's a HUGE variety fit for anyone, book lover or not, of used and new books at at least half the price of Chapters/!ndigo.
A few issues:
The staff can be quite rude, snobby and arrogant
There is no inventory system
Generally the books are minimum a few years old
That being said, it is my number one destination for any reading material.