I think what @fm meant was to buy a gift card that you can directly use with the merchant with Bitrefill. So I buy NTUC grocery (supermarket) or GrabFood food takeout (super app) gift cards from Bitrefill. These gift cards are directly stored on my NTUC n Grab apps and ready to be used when I need them.

You can check out whether the list of merchants available on Bitrefill suits your needs.

The Bitcoin Company also allows you to buy gift cards.

You probably lose some money due to processing fees this way, but with the Bitcoin I earn from the Cointiply faucet, I transfer it to Gemini, convert it to fiat and then send the fiat to my bank account.