In reply to ArranChild:
Alan can answer this for Rockfax but basically, I think it's because the "franchise" for each area's definitive guidebooks is effectively "owned" by someone. So:
- Peak District - BMC
- Lakes - Fell & Rock Climbing Club
- Scotland - Scottish Mountaineering Club (or whatever it's changing its name to)
- Wales (and lots of other bits) - Climbers Club
This is historical although it has changed slightly in recent years; e.g. Gogarth definitive now being commercial rather than Climbers Club.
It takes a lot of work (mainly from volunteers) to do a definitive guide and commercial producers such as rockfax are usually unable to concentrate this amount of resource on such a small area. Also there is the question of being in direct competition with the existing producers (usually clubs) where the profit (if any) goes back into the club to (hopefully) the benefit of all its members.
Post edited at 08:23