Do you have any idea what is required to release a title? Do you think every hardware vendor, software manufacturer and every other 3rd party profiler has the time, resources and commitment to send teams to every single development hourse, or publisher to do compatibility testing for each game release? Conversely, do you think these developers, publishers and especially the smaller companies have the resources to 'put up' these people while it takes the time to work on the title? No. Unfortunately, sending out alphas to these companies is a reality that has to be dealt with. Gone are the days of shareware demos and games that ran on any system. Further, UT2003 is one of a handful of games that's also pushing system and hardware limits. These things need to be tested as much as possible.
You want these games to play on YOUR system of course... well unfortunately in PC development, if you want a large percentage of the population to play the game, publishers and developers are forced into relationships with IHV's and other companies. Of course there are legal agreements in place, but as things go, there's only so much control that can be exerted.
Very rarely can any company or publisher do this solely on their own terms, there are so many players involved when it comes to these things. Even then, it is usually a matter of delaying the inevitable. I don't think anyone that has put probably endless hours into a game, or any of their work enjoys having to relinquish control over it; but in the end for the final product, these things need to happen.
Is there more that can be done to prevent this from happening? Sure, but that too takes time and $$$. I think over the next few years, leaks like this will be less common; however I really doubt they'll be eradicated outright. There's just too many hands in the pie!
-Dm