In poverty, you are getting through day by day, week by week. You think a week ahead.
In the middle class, you are putting away for college and retirement. You think to the end of your life.
The wealthy think of wealth generationally.
I think this is different for immigrants. The ones I know definitely think generationally. Regardless of the county of origin, they're thrifty and focused on improving their children's/grandchildren's lot in life.
I think that everyone likes to think they're thrifty. I know I do, but I still want to go to WDW, the Unthriftiest Place on Earth.