In any society, the slackers tend to coast and the overachievers go whereever they have to go and do whatever they have to do to get what they want. The immigrants we see here in the U.S. are not the slackers from their nations of origin – they are the overachievers or else they wouldn’t be here.
Many immigrants are largely familiar with that quaint notion of sacrificing now for what they want later. They trade the consumption of disposable goods for the consumption of RE. Not necessarily more virtuous, just a different set of priorities.
If you want to skim on your taxes, you’re not going to have the opportunity to do so by remaining in the employ of a company that reports your income to the IRS. A lot of immigrants know this from past experience at home. They know they need to follow the lead of the American merchant class and do it the good old fashioned way, by opening their own business and skimming the profits off the top.
Having a houshold income of $80k a year isn’t necessarily living poor if the top $20k isn’t taxed.