E-Scooter Accidents

They are illegal except in areas trialling them, and there you have to use the communal ones, not your own. I assume this is so they're serviced and insured.
Police round here do not confiscate them, they (and I quote) 'educate' the rider, who are uninsured, and who then ride off on them, having been spoken to by the police.
Anyone know if e-bikes have to be insured?

They may be very handy for people to get around in towns and cities but the riders are totally irresponsible, riding on pavements and riding with two people. How to stop them? That is something they need to work out! Both e-scooters and bicycles need to be registered and somehow find a way to hold them to account when they cause an accident. It's all to easy for people to ride off and no-one knows who they are. Bicycles are just as bad, riding on pavements which is illegal but who cares.

I don't understand how they can be registered if they're illegal.

That is a very strange statement Caleo. Presume you mean the people who ride e-scooters but not entirely accurate. Many people who ride them do not have accidents but the ones who ride them on pavements and winding in and out of traffic without looking are irresponsible and dangerous. In my area a lot of youths ride them dangerously on footpaths and are risking seriously injuring a child or old person.