I don't think unions are quite as anti-meritocratic as some people would suggest.
Two points: seniority is a huge determinant in who gets to do what in most union shops. This is anti-meritocratic. Unions routinely protect terrible employees from termination, not only because unions can be weak and corrupt, but also because unions are at risk of litigation if they fail to take reasonable steps to protect a member. This is anti-meritocratic, as the weak employees are essentially dead weight being carried by the better employees. If they could be weeded out, productivity would inevitably rise, giving justification for rising wages.
There is also the argument that by sponsoring a less acidic workplace, unions improve productivity. From personal experience, I have met numerous skilled and deserving unionized workers.
Huh? Most unionized environments seem more political than non-unionized environments. Pity the teacher that makes the mistake of taking a non-mainstream view in the staff room.
Also, getting in trouble for doing something like moving chairs around a room, because it is technically someone else's job is insanity. At least for me, this kind of environment would be very difficult.
I don't know why you brought up the second point, however. There are skilled and deserving employees in just about every company. I get the feeling that unions tend to hold these types of people back, rather than reward their superior performance. Public unions may be different in this regard, but all else equal, if unions didn't protect the deadweight employees, the skilled and deserving would be better off.
If the city was forcing CUPE employees to work 15hr days in asbestos filled attics with no lunchbreak, then striking is warranted.
Labour laws, not unions, are what protect employees in these situations. You have the legal right to refuse any work you reasonably deem to be unsafe without retribution. Employers are legally bound to allow lunchbreaks. Perhaps unions help ever so slightly in that they may stand up to employers who violate these laws, but I don't think they are by any means necessary for this purpose. Many, many non-unionized firms are held in check by these labour laws.