I don't see why not, if it has enough funds and the "delivery" country is the same as it was issued in.
They are vulnerable things to scams / theft though - so sometimes gift/refil/prepay "credit" cards are put under extra clearance scrutiny. There have been well documented instances where they have been intercepted in the mail, or scanned and "declined" at point of use (forcing another method of payment) and then massively cloned and used at coordinated times. Free money for the crooks.
YEah I'm aware of all those things. That's kinda why i was wondering, haven't seen a checkout system like theirs before... (well i have but that was in the 90's...