Listing
GW1 does not have as complicated an economy as GW2 – afterall, GW1 is not a traditional MMO. These fees are put in the game as a gold sink to combat inflation.
As for not giving you back your listing fee – it’s meant as a deterrent for people to use the outpost as a free bank. If there was no listing fee, I would list every single item that is currently in my bank for 999g. Obviously no one will buy it, and that’s the point – I would use it as storage.
If everyone did that it would lag the trading server.
It also encourages you to properly price your items. Price it too high and you risk losing your fee.
[Currently Inactive, Playing BF4]
Magic find works. http://sinasdf.imgur.com/
The fee is actually split. I believe it is 5% for listing. Theoretically if this were a real market you could say the 5% is for using the infrastructure of the exchange to reach potential buyers.
Then when you do sell an item, you get charged an additional 10% commission fee.