That isn’t just motivated by greed. In a competitive industry, if you take your foot off the gas, a hungrier competitor who is willing to go home at 5pm or 6pm will eat your lunch.
It’s partly a product of capitalism within a nation, but also a product of the basic struggle for wealth and power at the international level. This is a common discussion in my chosen industry; we have well paying jobs and good working conditions, but only because we are (significantly) ahead. Our lead, and by extension the good life, could completely vanish in five to ten years if we stop pushing forward.