>more USians move to my "poor" country than the other way around.

Retirees and people who already made money to outbid the locals on housing and purchasing power.

Why would they move to a more expensive country where they'd feel poor?

Emigrating is not an easy task (even with money), think why they do it and why the don't want to live on the country they were born.

Think about it... a hint, it's not about money.