LPS for phamENG for a good explanation of the US' standard. IME most white-collar management stateside are the aforementioned salaried-exempt (from OT pay), at-will employees. The reason for that is simple - we do NOT want our pay limited by arbitrary measures. Top paying employers all require proof of your work ethic so graduating early, working long/difficult hours, willingness to travel, etc are all big levers to pull in salary negotiation. 40/week and/or paid OT both come with mediocre pay, so hopefully the rest of the employment package is worthwhile to those considering that. Also, an interesting irony worth noting is that the folks decrying "unpaid" OT usually also decry executives for their high incomes and blame their own lack of success on others.
Call me odd, but I dont understand the obsession with 40/week. I spend an hour in the gym/pool/running daily, cook and/or enjoy two formal meals with family, spend 4-5 hours nightly in my shop, and can still work 10/day without feeling busy. How much free time does one need? Usually when I hear gripes about being overworked, its from folks who are pretty lethargic and dont have much for hobbies beyond television.
FYI for folks overseas, four weeks paid vacation is pretty standard stateside for engineers who have been in industry more than a minute, and 6-8 arent uncommon. If someone wants additional time off then a simple request for unpaid leave is usually quick and easy. Sick days and appointments are usually just a quick call or email to the boss, nothing formally documented. If I am in the state, I usually attend my wife's appointments. I haven't lived in Oz, but after living on four continents I honestly find both the pay and benefits stateside far better than anything overseas.