Background:
So, I just passed first month of working for EMC (Electronics Manufacturing Company) on conveyor belt, putting me standing for 12h with 15-25 min breaks each 2-4h in a room that feels like a summer day, but at least there's AC. All my co-workers, I don't understand how and why, have a mindset that, I should work overhours because I own them that, for the free transport, and for 2x money. But, the agency through which I'm hired (temporary employee), told me that overhour days are optional, and i don't need to be there. This way, if the schedule is favourable, I'm working only 3 days, 12h each, night/day shifts, with 4 days free. Or 4 days of work but with only 2 in a row, and then 2 days of break. The Quality Controler that's with us there though, told me that I might get fired for doing this.
But I really don't care about overworking myself for some more pieces of paper and metal. My values put free time over job time…
The questions:
Can I really be fired for not doing overhours ? Can the company punish me for doing 36h a week, not 40h even if schedule allowed me to ? Am I in the wrong here ?