Yeah, such services are using authorized sellers of course. As I said it really come from Amazon and its borderline system
So who and what counts as an unauthorized seller?
This thread has me a little concerned - not because I think Bitrefill will scam me (I've used them probably 100+ times for at least a dozen differnet retailers without a single issue) - but because I am worried that Amazon will arbitrarily lock my account with no recourse available simply for using legitimate gift cards.