Don't know, perhaps it is the motivation to survive and to fight for a better tomorrow.And many are still under educated today and still do the same jobs than the first generation did. Vibrant and highly educated and financially successful are terms that have different meaning, are you aware of that?
My cleaning lady and her husband (from Central America, uneducated), clean houses 10-12 hrs a day 6 days a week. They earned enough to own their own home, drive a late model car. My handyman came from Asia as a refugee 10 years ago, didn't even finish high school back home, still speaks limited English, he and wife work as a team, work 7 days a week, no breaks, and already owns a remodeling business and owns a home. Daughter is graduating from college.
I am sure there are plenty of immigrants in LA that day in day out struggle to survive, to get out of poverty. Give them a chance to work, even for peanuts, few would refuse because compare to where they came from it is infinitely better and they all have hopes that life can get better.