I am surprised you have received no comments so far!
Another two aspects to the traffic/manners problem:
a) Not all drivers realise the need to slow down when passing horses - whether they are being ridden or led,
b) Similarly, there is a tendency for drivers to forget that if cars are parked on their side of the road they should give way to oncoming traffic
(which needn't necessarily say "thank you") but who often do - isn't that nice!!
