"An honest day's work for an honest day's wage" sounds right up my alley, but thats an old fashioned way of thinking these days, especially if you're talking about physical labor, which I don't do. I have before, but I don't do it now. But the sentiment that you should get as much as you've earned seems fair. No matter what you do, if you do it well you should be paid well. In the case where your wages aren't any higher or lower than anyone else's, "give 110%" is another sentiment I believe in. It leads to better security within the business, raises may come sooner as will promotions.
But in turn, when you recieve these extras I think you have that much more responsibility to prove to your employer that you deserve what you have.
I think it should all be considered proportional. The honesty and thorough completeness of your tasks and job, and the ammount of money you earn.
If something is out of balance then someone is losing unfairly, either the employee or the employer. Its a win-win situation when the employee and the employer have a mutual understanding of their business relationship and both watch out for eachother, take the other seriously, and respect eachother.