Why are the unions so hostile towards the voluntary sector?

On Wednesday night I was at Lambeth town hall in Brixton, south London, where around 150 protesters occupied the council chamber during a meeting, forcing councillors to leave.
 
Lambeth Town HallThe council meeting was to pass a budget that contained cuts of around £79m over three years. Once the councillors had left (to hold a private meeting at which the budget was passed), the protesters declared a “people’s democracy” in which everyone could voice their concerns.
 
One of the many things that struck me during the protesters’ meeting was the unions’ reluctance to let the voluntary sector run services. When the protesters started talking about a council plan to let voluntary and community groups run the borough’s playgrounds, the reactions ranged from scorn to pity.
 
“The voluntary sector just can’t run our playgrounds, no matter how well-intentioned it is,” said one of the town hall occupiers. “It’s just not capable of doing it.”
 
Others took a more hostile approach, muttering loudly about voluntary groups “taking jobs” from the public sector.
 
I hadn’t realised until last night how much of a problem this could be for the sector. Charities are under pressure from both sides of the political spectrum: those on the right think they shouldn’t get state funding in the first place, and those on the left think that when they do they are undermining the public sector.
 
Lambeth Town HallThis could be a particular problem in Lambeth, where the council has a radical plan to become Britain’s first “co-operative council” in which services are provided by voluntary groups wherever possible.
 
But I’m sure it won’t be limited to Lambeth. Reluctance, or in some cases open hostility, from those in the public sector – particularly when their jobs are at risk – must be making life hard for voluntary groups across the country.