I agree. Although they don't have paper copies to give you, you can see and print the same maps at the RATP site under the heading "Plans de lignes" (only available on the French version of the site, not the stripped-down English one). Choose "bus" and then the bus number, and a .pdf of the route map will pop up.

I'm not sure if there's a bus route map book with those particular maps or not; I'll try to remember to look next time I'm near a bookstore. I have a old blue one by l'Indispensable (Le Bus: Répertoire des 80 lignes) which is better than nothing, but the print is tiny so it's hard to see where the stops are.