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Some people seem to take issue with the idea that others are willing to spend their hard-earned money (or their parents' money if that's the case) on a game that's still in beta, under at least a partial NDA and has no release date. Here are my reasons:
1) I have been playing GW1 for 5 1/2 years and it is still one of my all time favorite games.
2) As far as companies go, Arena.Net is one of the better ones, IMO. Mainly because they seem to be pretty fair minded in their pricing and I have yet to see them reneg on their promises. In short, I trust them.
3) No subscription fee. For me this is a big one. There are many, many games out there I would love to play but, on principle, I refuse to pay a sub fee for a game.
4) I have looked at many gameplay videos and they all look pretty awesome. Not to mention fun.
5) The lore.
6) The different playable races. I love the norn!
7) The items that I've seen in the Cash Shop don't bother me in the least. (Not to say it couldn't ever, but I'll cross that bridge if I ever come to it)
8) I've been looking forward to Guild Wars 2 since they announced it, so this is one way I can get a step closer to playing it.
9) Because of the above reasons, I was going to buy the game anyway, so why not do the pre-purchase, get guaranteed access to the beta weekends (haven't ever done that, so I'm pretty excited about that), and the three day head start - so I can start playing for real even sooner!
So, what were your reasons for pre-purchasing? Or, if I'm walking over your bridge, feel free to berate me for it.
Disclaimer: #7 is only there to illustrate a reason why I pre-purchased the game, NOT to start another flame war over it, so please refrain from doing so. Thanks.