post scriptum:
it finally dawned on me!
Britain, Wales and Scotland still got the English upper and high class system embedded in their culture.
Och I was slow to understand that!
That why the Scandinavian and Dutch people here dont get it!
"Britain, Wales and Scotland...." not yet but give it a couple of years!
Presumably the unwillingness of Dutch and Scandinavian people to work other than for cold hard cash means that they can't get volunteer moderators for their bushcraft websites so have to use ones modded by downtrodden serfs in the UK. I guess bushcraft gettogethers never happen there either because no one is prepared to spend unpaid time arranging them?
Ironically, volunteering does potentially damage the interests of less advantaged people, but not in the way (I think) that you are suggesting.
Kids from poorer families are less likely to be able to afford to take unpaid internships (or have the social contacts to arrange them) or to pay for voluntourism opportunities to decorate their cvs to get the best education or job offers. The willingness of volunteers to work for free for the National Trust, local Wildlife Trusts etc. obviously reduces work opportunities for professional gardeners, foresters etc.
Sorry to burst your theory but, if you spot someone working for nothing in the UK, they are as likely to be towards the higher social echelons as the lower.
PS apologies, I typed this a while ago and got chatting with Mrs Nomad about some unpaid work she had been doing arranging an Easter egg hunt - I didn't realise that there had been a voluntary (can you see what I did there!) end to this thread.