The problem in the UK is a general lack of respect or tolerance for anyone who doesn't do what you do.

I am (for my sins) chairman of Southern Group TRF so am quite involved with the "Green Lane" issue.

I hate to see a torn up bit of countryside the same as the next man but the off-tarmac lanes network should be sustainable in the UK. What is happening though is that as lanes are restricted, other lanes become over used, which in turn leads to them being damaged and then restricted.

4x4s
The 4x4 drivers don't do themselves any favours. There is a fine old, tree covered sunken lane near me that has some big rock steps and is a challenge on a bike and bloody difficult in a 4x4. What happens is 10 4x4s pull into the lane to try to get up, spend 2 hours winching and digging then give up and cut through the woods and accross a field to bypass the steps.

Walkers
We regularly meet families walking with there dog and the parents will normally smile and nod a hello and the kids will wave.

Ramblers
They just don't look like they are having any fun in the countryside at all. What a sour-faced bunch of ignorant w***ers. They seem to relish a confrontation and are very put out when I talk to them politely. I don't understand why they walk down a lane that is known to be used by traffic when there is a footpath 100yds away that goes in the same direction. When I get any evil looks, I like to stop and explain that they really need to understand that they are walking on a legal road and that I have past a bike test, got an MOT, Road Tax and Insurance in order to be here. If they don't like meeting traffic, they should walk somewhere else and not down the middle of a road.

Horses
Most riders are sensible and will find a spot to pull in to allow us to overtake. When they are coming the other way, we stop, cut engines and let them pass. I've never had a confrontation with a horse rider. Our club often employed to set out courses and marshal equestrian events.

Damage
There is no denying that a motorised vehicle has some impact on an un-surfaced road but even when the recreational user is restricted, agricultural vehicles are not. A lot of the lanes that have been "closed" are still in use by heavy forrestry and farm vehicles.
Lots of lanes that have been closed for just over a year have now disapeared. They are overgrown and impassable by anyone.

Recreation
If I want to play football, there are 20 or more public pitches I can play on.
Swimming; public pools.
Skateboard parks, tennis courts, etc, etc,
All funded by public money for public use. Would it be so difficult to leave a few lanes open to all users.

Sorry for the long-winded rant