To be honest I didn't use my Bitcoin as a payment regularly. Sometimes I used it occasionally when I saw that the market was pumped price.

The most important thing is, of course, the brand name of the merchants that already well known and trusted enough for your orders and fast shipping even worldwide(but I prefer on local merchants). This is the reason why I use Bitcoin occasionally as payment because of the high fees. Maybe if merchants allow using Lightning Network for Bitcoin payment that can transact micro payment it is a good idea.

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I like what have said the post above that merchants will not use the same Bitcoin address, it will automatically generate a new payment address when you having a payment.