I think they have considered why, and they choose to dismiss it as weakness because that's all they really care about: projecting strength and power. If they don't complain about not getting paid for ALL their work-related responsibilities, they will be seen as weak by their employer and might get fired. So they lean in hard. It's a brutal self-perpetuating system that eats people alive.

Anywho, you might be interested in /r/antiwork and /r/workreform if you haven't dropped by already.