A third reason might be the argument from market power stemming from the fact that if you can personally create $10 million of cold hard cash value using nothing but a bit of time in front of a computer, and with no long-term detrimental effects on you of any kind, then the fact that you are minting money creates a seller's market (just as there will always be a seller's market for legal currency), and it [might be an argument for] allowing you to work whatever hours you wanted - or sleep in the office, be offered legal drugs, whatever. if you didn't like it you could go somewhere else.
it's very different if you were cleaning staff at any of the same companies. they "need" more protection than you do!
Edit: from your responses it is clear that many people it applies to should also be owed overtime. I was just throwing out one "logical reason".
In addition I've thought of the crazy hours residents and doctors put in - so that high earnings / value add might not guarantee that much market power, if the conditions are the same at all hospitals.
on the other hand much of computer labor is absolutely in a seller's market (from the point of view of the employee) and clearly does not need the same level of protection. there is a lot in many workplaces that a "computer professional" wouldn't put up with for a second.