$5 in the Philippines probably has vastly more purchasing power than it does in the United States. If you’re supposed to pay them the same salary as to someone working in the US then why not just hire an American and have the dude in Philippines go back to picking coconuts for $2 and hour or something. I wouldn’t be surprised if the Philipino worker is more than happy with their salary and you might even be able to employ several people for the same amount of money.
This same effect applies to charities aswell. Donating money to some poor african country helps many more people than it does when given to a local charity.