Remember that 50 hour beta registration event? People who signed up during that have a chance to get into the beta weekends.

Also, betas have not been just for testing for at least half a decade now. There are still testers in betas, usually before the public even has a chance to sign up. Some of the public will be chosen as true testers as well, but larger, later stage betas are now used for marketing. PC demos pre and post release are basically nonexistent anymore. The marketing beta has taken up some of the slack for the loss of these demos and honestly i think many publishers prefer this. An open demo close before or after release, with no termination schedule doesn’t get people going nuts like the marketing betas do. With limited timeframes and often periods of limited invites, hype and interest are generated more easily. I really miss having all those PC demos around for even years after a game was released, because renting PC games is just not common like it is with console games. 

 Based on what i said before, I’m fairly confident you weren’t actually testing Diablo III or SWTOR. You most likely weren’t there spending hours finding bugs and having a personal discourse with the development team. They weren’t relying on you as part of their small team to give them daily or weekly updates on what you’ve found and how effective their changes or fixes have been.

You were there as more of a lab animal, not an intern. They gain information in these marketing betas, sure. Information about server stability, game imbalances, quality of content. The beta test just doesn’t mean what it used to in many cases. True testing is not just getting to play early. You’re not really playing in the same way when you’re really testing something.

The marketing beta obviously works. It hits the desire to play something before others and allows people who participate to get some idea about if the game will be a good financial investment for them. Obviously being betas–usually not as close to the finished product as a demo, there is a clear downside when it comes to judgement about future purchase.

I definitely see where you’re coming from, but I don’t share that viewpoint. If you have followed this game enough and you’re very confident that you will enjoy it, then the pre-purchase is worth it to you. If that doesn’t apply to you, then you should not feel any obligation to pre-purchase or any resentment towards ArenaNet or those that do pre-purchase. Anyone who is afraid of pre-purchase because they don’t think the game is EVER going to release shouldn’t be pre-purchasing in the first place. I certainly understand since you seemed to think that only pre-purchasers can get into these beta weekend events. If that were the case, I’d definitely be more sympathetic to your point of view.

If you aren’t sure if you want to play the game, wait for it to be released, read some reviews, and then make a decision.

If you are confident that you’ll want to play the game, it makes very little difference whether you pay for it now or later. It makes perfect sense to prioritize beta access to confirmed purchasers; other people could be using the beta as a “demo” and getting a misleading image of the game (which is still buggy and incomplete), leading to a reduction in sales. So the alternative was between a beta that prioritizes “confirmed” buyers or a closed beta.

If you aren’t planning to pre-purchase, then both options would be identical to you. If you are planning to pre-purchase, then the second option means you can help iron out some bugs and make sure the game is released as soon as possible. It’s not like they’re deliberately delaying the game’s release; they want it to be ready ASAP.

If what you want is a game demo (not debugging / beta testing), then just wait; I’m sure they’ll release a trial version, eventually, like they did for GW.

The SWTOR beta gave priority to people with pre-orders and the Diablo III beta gives priority to people who bought the WoW annual pass. Since the servers have limited capacity they’re obviously not going to give random people (who might not even bother to play the beta, let alone buy the game) priority over the ones that are willing to “put their money where their mouth is”. AFAIK, you can still get into the GW2 beta without pre-purchasing (at least until the number of pre-purchasers hits the limit, but then ANet will suspend pre-purchases, which hasn’t happened yet).

GW2.exe (21 MB)
GW2.tmp (0 bytes, used to download updates)
GW2.dat (12.7 GB, the game data)

Plus a couple of very small optional files if your game crashes (crash dumps and logs).

The game creates a couple of other executables in a temporary folder when it runs, but those are pretty small.

Best of luck!