The reasons to care are personal pride in the quality of your work, understanding that your lack of effort has a negative impact on your colleagues, and your continued employment.
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.
If you can't find a better job, you should probably appreciate the one you have and not try to skate by with the bare minimum, if for no other reason than you're likely to miscalculate at some point.
Ah, noble poverty! Be grateful to tha masta' for providing you the scraps he can provide! Your paycheck is the beautiful work you produce for tha masta'!
Seriously, pay people what they are worth and they will care. It is not that hard.
The vast majority of people significantly overestimate their worth, yet people with your attitude seem to believe it only exists with respect to highly compensated employees.
I agree with your second sentence, but it's harder than it should be due to what I said above.
Pride in the quality of my work is a phrase to make one feel bad about themselves. I take pride in my hobbies and in my hobby projects. I take pride in my family and friends. I do not take pride in being exploited for my work so some higher up can buy a new car every year.
And again, someone comes and makes a comment that proves my point. Unless you are working in very unusual (and illegal in the developed world) circumstances, you are not being exploited in any real sense.
In the end this depends on your definition of "fair". What percentage of your generated production do you think is fair for the company to take? 95%? 50%? 10%?
That depends on the value of your generated production, among many other things, and ultimately isn't the right question to ask.
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.
You were talking about exploitation. Using the fact that the employee cannot obtain a better employment elsewhere to extract as much of the production or value from the employee smells a lot like exploitation to me.
If an employer offers an employee $100 per hour, and the next best offer that employee can obtain elsewhere is $90 for an otherwise equivalent job, should the employee take that job for granted? Is the employer exploiting them with their pay rate?
In my humble exploited worker opinion, you resemble Samuel L Jackson in Django Unchained. You dont even realize in what position you are in. Get back to the ground bootlicker.
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.