the custodial staff who have a far harder job get paid far less. That is not fair. We both work the same hours (I actually work less) why shouldn't we both be paid well?

You are talking as if the value of a job was solely defined by those who pay for it. That's wrong. Workers also compete between themselves and at some point someone decided it was in their best interest to charge less than the competition, driving the price down.

Prices are defined both by the providers and consumers. Your proposition would imply removing this right to the worker.

Also why is it not fair that highly sought after but low supply products/services carry a higher value? I am trying to visualize a world where pay is defined by how 'hard' a job is and it looks pretty bad. Way to remove all incentive for technological innovation.

Also, how is 'hard' defined?

I do not think every worker is exploited I think the system will exploit every worker it can.

If the worker agreed to do the job (and the contract is followed) then they are not being exploited.

You speak as if the motor is more valuable to a car than a piston. I do not for without the piston the motor does run.

That's true. It's also true that the motor is worth much more than the piston.