After the American service is launched in Hong Kong, it no longer supports domestic single-currency Visa, MasterCard, domestic dual-currency credit card and domestic paypal. The only support is Baoka, so of course, if you have a local bank card in the United States, you can still pay.
American state consumption tax/sales tax consists of state tax and local tax. Local taxes are formulated by the municipal government.
Some tax-free states grant tax exemptions according to different kinds of goods.