Why are weapon skins still one use?
Regardless of the merits of any particular idea, ANet can only work on and implement so many changes. Some that sound simple (like making skins re-usable) often involve more work than we think.
For example, a sensible way to implement this might be to create a locker for cosmetic items. But that involves more coding than just making skins soulbound. Similarly, if they do start making multi-use skins, how does that affect people who paid 100s of gold for skins when they were one-use? Or people who sold skins, because they were only one-use?
So, independent of any economic reasons that NCSOFT might have, there are all sorts of reasons that skins might continue to be one-use.
People can keep making the suggestion, but I don’t expect ANet to comment on the idea until/unless it’s scheduled for release or they firmly decide that it’s never going to happen.
Also you’re more likely to buy more gems to buy more chests trying to get a ticket this way. A pretty cynical viewpoint, but I’m convinced that it’s at least part of the reason.
Considering you pay a premium price for skins, i agree that they should be in the achievement tab where you can pull one out at any time, as many times, for any character.
You easily payed an equivalent of 10euro’s for a single weaponskin. Then milking it by adding a vertical gear progression (ascended), or “rebalancing” stats, so you want to use a different item, just so you pay more then once for the skin you already payed quite a lot for.