The same kind of people who....
...spend 4.5 million pounds on a website?
...aren't able to handle the traffic for a popular release?
...don't get preorders up on their website until something's already sold out?
...don't seem to grasp that people can't find redirects if you don't have them live?
Also, you can test all day and people will still find a way to break your software. And I have no idea how much they do test. I just hope it's a lot more than the game development team.