It is fatal for any body of workers to have forever hanging from the fringes of its skirts other bodies on a level just below its own; for that means continual pressure downward, additional difficulty to be overcome in the struggle to maintain reasonable rates of wages.
To overcome cultural resistance I think it's important to start with strong analysis, so you're sure that you're right about what needs changing or fighting. And then you have to articulate the best case you can and start working patiently to build support and to mobilize allies.