I know doctors who live a modest lifestyle, so it can be done. The leader of a band that I play in was an ER doctor for a while, then got a job at a walk-in care clinic, and retired at a young enough age to enjoy his retirement. During this entire time, he lived in a modest house, and mostly rode his bike to work. He lived within his means like the rest of us.

There's no law that you have to live a rich lifestyle. Part of that may be feeling the need to maintain the class status that you were born into, and that you expect your kids to be born into. Case in point, my friend came from a working class background.