The idea is that tracking it is effectively impossible for a foreign government...and we've made that whole infrastructure incredibly easy via making it legal for LLCs to purchase homes. We don't prevent foreigners from forming LLCs, and often times there are brokers that make their vig on doing just that for wealthy foreigners - they set up a myriad of LLCs to protect the identity of a buyer, who then drops $1mm+ on a property that they will never actually use in a country they will likely never visit.

Plus, to buy stocks or ETFs or bonds or whatever, you have to register with a broker, who has to legally report each sale and transaction to the government. The point isn't the liquidity. The point is that a family can drop 200k-500k in a pretty stable asset in an incredibly less volatile environment and effectively not report it. That is worth it in the age of hyperinflation in LatAm economies. Plus, if the unit in question is in a decent location, they can escape at the first sign of trouble.