You must register to collect and remit the Quebec sales tax (QST) only when you have operation in the province (such as production or marketing activities), when you hire an employee and/or when you have an address in Quebec. Otherwise, you are not obligated to collect QST on behalf of the province if you sell taxable goods and services to residents of Quebec.
从网上找到的
看来商家是故意收入自己的荷包