Selling game cards for ingame gold

As this is referring to a Game Card, as in you purchased pre-paid time for a World of Warcraft account — and therefore it is only a real-world currency reference, and are unable to do anything with it in-game — I would recommend avoiding doing this. This could very easily be considered the same thing as purchasing gold for real world currency — as you essentially are.

Laeli, m'dear, he is talking about the pre-paid Game Cards. As in the cards that you can use for subscription time. ^_^