[rahimnathwani]

Used books in France appear extremely cheap because new ones can't be discounted. By law (I think) retailers only allowed to offer a maximum 5% off.

Used books are exempt from the law entirely, so they're priced by pure market forces.

In countries like the US or UK, a recently-published book might already be 40% off list price, so used copies may not be as much of a bargain.