2. It's hard to work full time and go to school after. It's by definition going above and beyond.
No, I don't think people are being too lenient -- it's a bit more subtle than that. There are many physically demanding jobs, some as much or more so than warehouse worker. I was questioning why we never see people say people in those job families couldn't possibly study after a day at work.
What you want to do is also irrelevant, as you might have an enjoyment of carpentry. Me, I hate it, and would rather be a warehouse worker.
And you've just made my point for me. "Most" other jobs. It's not the most difficult, most physical, most dangerous. Where are the people saying people in job "X" can't possibly study after a day at work? Somehow, that reasoning is confined to warehouse workers.