How is this not hilariously illegal? This is also a great way to walk into dozens of egregious customs violations if you use slash and happen to import physical goods in the united states for sale or distribution.
You have to pay U.S. customs with a U.S. bank account - specifically to hold funds in escrow.
Developing ways for businesses to conduct transactions in the U.S. and more easily extract remittances without a tax id or bank account that's a part of the U.S. banking system is beyond stupid and borderline criminal.
If you do your risk assessment well, it can be good tool compared to traditional banking