It's not necessarily maximizing money, but maintaining lifestyle. It's extremely common for people to increase their standard of living as their means increase, and reducing that requires significant effort in some cases (e.g., people tend to buy as much house as they can afford, so any significant salary reduction could necessitate selling the house and uprooting your family). It's a minimal sacrifice in the face of having to work a job you hate, IMO, but it's still a powerful barrier for many.