Americans work so much, on average, not because they are greedy or because the want to work.
They work because there is so many who do not work so hard. Those who do not work so hard are, as a rule, fueled by the taxpayer collected money. It has already been proven, without any doubt, that, on average, governmental job pays way way more than private job.
Have you heard about NJ cops making $100K or $150K? Yes, I agree, that $100K is not that much money, however it needs to be taken into account that cops need to work 20 years and then they get taxpayer funded pension and medical benefits. I am not trying to bash cops, or single them out. If US GAAP rules are used (meaning US Generally Accepted Accounting Principles are used), which means that expenses need to be accrued when incurred, such jobs would need to be accounted as costing not $100K, but $200K, for defined benefits (pension, medical) need to accrue at the same time. It is not even the largest issue. The larger issue is entitlement culture and "social" payments to the population which traditionally keeps voting for politicians who keep promising more freebies and benefits only if you vote for them.
One and only one conclusion comes to my mind: The taxation level. Some might say that those socialist Europeans pay more taxes, however there are some very important differences. For example, in Europe, as a rule, schools are funded from federal budget. In US schools are funded from property taxation, except for low income areas which, logically, cannot afford their schools and get funded from the state or federal funds. This leads to de-facto segregation in United States by school districts, that nobody likes to talk, yet everybody knows. Low income areas have few meaningful jobs, which leads to many non-working Americans living here. Higher income areas do have high property taxes which automatically do add additional hours for higher living standards need to be maintained with additional work.
The truth is that current taxation system is the primary driver of the human behavior. Some people will continue working to death and other part of population will keep continuing voting for the status quo that allows more tax benefits, irrespective of the economic class of the voter, be it Dianne Feinstein's husband ingenuity winning profitable real estate business related contracts, whether it will be teacher's, police or FDA "scientist"'s benefits, or generationally unemployed welfare receivers.
That is taxes, baby!