Drac, whilst I understand why you posted that I think you are predominantly (if not totally) preaching to the choir here [metaphorically before it starts a religious debate]. The downside is that when we send out these 'don't waste our time' messages to the 'good' people we plant a little seed of doubt. Should a broken arm in the middle of nowhere merit a call, or perhaps I should try and drive with my one good arm - I'll probably make it? Should I call for the "drunk" I find in the street? or perhaps he's hypo or will not wake up in the morning! Should my wife's 87 yr old grandmother call when her brother "has a funny turn" (which turned out to be a stroke) or should she call her son-in-law who is 25 minutes away and ask him to pop over later on to give him a lift to the doctor if he is not feeling any better? Or the normally healthy 34 yr old male taking antibiotics for a chest infection who is struggling to breathe and calls NHS24 rather than 999 and then waits for the doctor to come out (he was dead within 24 hrs). Should I call the police about the obstruction in lane 3 of the motorway? Should I call the police about the man lurking in next door's back garden at night? Or the kids 'tagging' the bus shelter across the road? Or when the neighbour's teenager is taking potshots at the cat with his air gun? Or perhaps Mr X next door has just come home from the pub and is throwing stuff at the missus again?
The "system" relies on members of the public calling in incidents. Some of those incidents might not be the most serious, might not technically be emergencies, or might have a perfectly sensible alternative way to resolve it - but I think generally nobody objects to those being dialled in as 999. The issue is the 'I need to get home' 'I've got no credit' brigade, or those who know the magic keywords to use ... But they aren't likely to be on here and aren't likely to pay any attention anyway. I'm not sure "education" is likely to be effective at anything other than putting off some genuine calls.
I'd like to see time wasters prosecuted, just as we would with hoax callers. I realise that is difficult and ties up resources but if the consequences of totally taking the piss are nil then you will continue to get that.