Make the routes freely available for download as GPX or KML files
The routes are shown on IGN maps, and posted on signs around the country - however you don't provide them in a form that's compatible with my GPS or smartphone. Why not share the routes freely in digital form to encourage more people to get out there and hike.
You can still sell the detailed guidebooks for those that speak French and want more detailed info.
Please bring ffrandonnee into the 21st century!