It's the 'last mile' issue. Every village was down some track a mile from a good road. Just the place you needed the bike to work. Most weren't going to Rome; just around the village.

And a modern 'regular bike' is maybe 100x better than the original wooden, wooden-wheeled non-steerable chainless coaster bikes they started with. Made of local wood that could split and swell and snap at a bad bounce.