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.
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.
What's the point of inventing a non-existent situation where you're obviously correct, other than self-gratification?