I don't blame you, inconsiderate parking, inconsderate road users... Having a Brother who is completely blind, a sister who is partially sighted and my ex partner who is also blind... I fully understand the fustrations of other users and its a minority (as it always is) that are the offenders.
Thats why these motor scooters need to have a proper DVLC Q plate, the user registered and to have a licnece to operat the thing. You have to have a licence to use certain vehicles that are used on construction sites despite the fact that most of the worling life is off road, so why not a 4 wheeler that is just as quick as a JCB on the road?
A 50cc hair dryer, often called a mophead has to be taxed carry a licence plate and the driver of it carry a licence, so why not motor scooters that are in most cases able to keep up with a 50cc scooter that is limited to 30mph.
I also do not think that these users should be using the foot path, only where it is for access. IMHO they should be limited to the road. Maybe then these users will have a bit more respect for other road users.