Let me get this straight. Do you want to sell the amazon gift cards you have? Or are you buying amazon cards from other people?
Do you not understand the concept of WTB vs WTS and the usage of the word "for"? It really isn't that hard, trust me....
Obviously This topic is confusing.
"WTS Bitcoins for Amazon Gift Card, AKA WTB Amazon for BTC"
"Technically what I am doing is the exact opposite"
The above statements contradict.
So, OP, If you Have the amazon gift cards and want to trade them for BTC, your title should be: "[WTS] Amazon Gift Cards"
If you have BTC and want to trade them for Amazon Gift Cards, your title should be: "[WTB] Amazon Gift Cards"