Perhaps the costs (when Bitrefill buy/obtain the gift cards) are different, even though it has same value (25 EUR). If you check other similar website (such as egifter, gyft or steamgamesbtc.com), price of gift cards with same value for different services are slightly different.
i've been using egifter and gyft for several years now. neither of them does that. like most merchants, they both give you the exact dollar price through bitpay, who uses bitstamp prices. no fee added. nothing like this where bitrefill generates their own conversion rate which is obviously way different than spot price.
the only difference with egifter is they award you points with each purchase which effectively work like discounts. each gift card and purchase method (bitcoin vs paypal) yields different rewards. but no matter what, you would never be charged more than the spot price, only less.
I stand corrected. I don't use both services anymore due to country restriction and looks like i didn't remember it right.
But regardless, it's common business practice, at least on services/merchant which i use regularly.
