Well, I don’t know. Let’s say a Bangladeshi guy earns $1,000 AUD and sends $500 home each week, then lives off the remainder.
He’s only contributing to the Australian economy $500 per week instead of the full $1,000 in bank-invested savings or other purchases. Meanwhile the other $500, minus an exchange rate, sits in another country’s bank or contributes to purchases there, fuelling that economy.
I mean, I’m guessing here. My economics knowledge is fairly limited.