Salaries track two things:
Supply: If something is unpleasant, dangerous, or illegal there will be fewer people who will do it. Construction workers, drug dealers and prostitutes can make some decent cash.
Demand: If you are awesome and your skills are in demand, companies will pay more to keep you. This is why a high-class prostitute can make quite a bit more than a street walker, despite the danger of street-walking that should limit the supply.
So yes, if working at your job is pleasant, you can pay your employees less. But if your employees are in high demand, you can't pay them that much less because the whole point of work is that you're exchanging how annoyed you are to have to be there for cash.
http://www.streetgangs.com/academic/gangfinance.pdf http://economics.uchicago.edu/pdf/Prostitution%205.pdf
And yeah, illegality and danger does limit the supply, but unfortunately not as much as it should. That's because these illegal jobs aren't competing with careers in computer science; they're competing with jobs at McD's. All they have to do is outpay that and the risk of getting caught, which is sadly not much.
A high salary means that your employer consider you to have high worth. They won't waste your time -- and they will try to keep you happy (you're a valuable resource).
Edit: I should add a corollary -- for job satisfaction, stay away from situations with too little money and hard competition for few jobs. (The academic world and bureaucracies comes to mind.) It is like too many rats in a too small cage...
Another question, about 60-80 hours work weeks:
I've always read/heard that 40 hours was a work "optimum". If you do more/less hours, the productivity over time will be less. Are high paid people generally able to work 60-80 hours a week over years and be productive?
(I wouldn't know -- I'm not certain that 40-hour rule fits me personally.)