I think it's great that it elicits that reaction in such a stark way, though - it will make more than a few of them wrestle with it and maybe get past it.
I can totally defend the desire to quit out of not wanting to have golden handcuffs, but quitting because someone "below" you is now not as far "below" you (or is now "shackled" to you, a ridiculous thought) is just spiteful and self-damaging.
I think it is - for the cited examples getting a raise from 40k to 70k, this is strictly better than what they had before,/but they're still complaining. Economic rationality has nothing to do with it.