Why USDT works for hosting in Paraguay
USDT holds its dollar value, so the invoice never drifts between the quote and the transfer. In Paraguay the alternative is a card billed in dollars against a Paraguayan guarani (PYG) balance. Local cards settle in PYG, so any foreign-transaction fee on a dollar invoice comes from the issuing bank.
Paying from a wallet takes the bank out of the transaction. The invoice is priced in US dollars, the USDT amount is locked for 15 minutes at the live rate, and the transfer goes straight to the address on the invoice. Nothing to approve, no merchant category to argue about.