And if you hate your job, but are completely unable to find alternative employment (which is what you should do if you hate your job), you probably should reconsider how much you hate your job.
Seriously, pay people what they are worth and they will care. It is not that hard.
I take pride in the stuff I enjoy doing. A job is just a paycheck because I need it.
At no point did I state or imply that workers should be working solely or even primarily for anything other than money.
But if you can't be bothered to take pride in the work you're being paid to do, you shouldn't be paid to do it for long.
Can an employee obtain better employment terms elsewhere (which is a complex concept to define in itself)? If so, they are underpaid, if not, they aren't.
I agree with your second sentence, but it's harder than it should be due to what I said above.
What's the point of inventing a non-existent situation where you're obviously correct, other than self-gratification?