^ actually you should call the cops on them - even on a bicycle it's illegal to be drunk.
as for the OP, if you wouldn't have been swearing at the kid I think you prob would've had a better chance to get thru his thick skull that his mother would've attended a funeral was it not for your son's ability to swerve. I agree with you, tho - I think it's infuriating the lack of knowledge these e-biker riders have - seems even less than bicyclists. I think it's yet other group altogether who otherwise wouldn't bicycle, so they know even less the rules of the road.
E-bikes are for people who are too fat/lazy to bike and get exercise, and too poor/ignorant to ride a motorcycle. Worst combination in my opinion...