I'll completely accept that some specific unions, almost always in concert with bits of government, get captured by organised crime in some places and then the market is then manipulated to serve neither the members of the union, or people represented by the government. This depends completely on the union and the government we are discussing however.

I would also accept that this may be partly the case in this instance, given the behaviour. [edit] Though I find it less likely after having read eli's brief comment on the matter.

That does not mean that unionism itself is the problem, but rather the culture of certain unions. In the same way that just because certain companies act badly doesn't mean that all do.