[yokaze]

A very American assumption, that a lack of regulation equates to more freedom.

In both cases, the individual is limited in their choice. Without legal restrictions, the individuals choice is restricted by economic and social constraints. E.g. in low paying jobs, less hours is not an option, because of low pay, and in "high" paying jobs, it isn't because you won't have the job long. Precisely because of the implication you give "more hours -> wanting to work harder". And partly because your employer doesn't want to go through the hassle of having to handle different work schedules, managing more people.

The "European" variant is a collective choice countering the socioeconomic pressure.

In Europe you are "forced" to have a medical insurance, in the US, you are free to choose/lose it with your employment.

I would claim, socioeconomic constraints are limiting your choices much more, than laws do.