I've seen suggestions that people should start carrying 2l bottles of cold water (OK I've also seen suggestions of worse contents like slurry or urine but don't think that necessary!) to pour over these protestors should you find them in the way of your car, and thus annoy them back without doing anything terribly illegal, like driving over them would be.
Also to have a bag of large cable ties in the boot, which could be used to secure them to nearby railings or lampposts (for their own safety, obvs) if they insist on running back into the road each time the public move them off to the side.
The fight back is coming, if the police continue to do nothing but offer them nice cups of tea, I think inconvenienced members of the public will soon start to take things into their own hands, but hopefully with harmless measures as above before someone is actually run over and squashed.