It doesn\'t take much effort to look around for your answers, really, and I recommend doing a bit more of a search next time ;)
The game is still in pre-alpha stage, so all you can do is collect crystals to buy decorative weapons, solve two quests when the NPCs are available (they often disappear for several days), chat and make friends, roleplay, join guilds, and explore/glitch. It may not seem like much for now, and if it\'s not for you, then you may consider waiting until CB, when more \"game elements\" will be added. However, the community is what keeps people here.
Why buy weapons? There\'s really no reason. I suppose it could have been looked at as a status thing, to show how good of a crystal hunter you are, but now after more than a year even galkards are seen too frequently ;) Weapons can be used for roleplay, too. They will not be saved for CB, although it is said that our character names and crystals will transfer over.