weeks - 1:11 pm on Oct 8, 2010 (gmt 0)
Ten years ago I worked with a scary-smart coder (PhD in computer science from a name school in the east, worked for DARPA for several years) with the ethics of Al-Qaeda. It took him four days, but created a script that jumped this kind of captcha and allowed him to download 99 percent of a db from a name everyone knows. To answer your question: Because of people like him.
The captchas I hate most are those within Google Analytics that you have to solve before you can send yourself a report about something.
C'mon, a user has to be already logged in to send themselves a report, what's the captcha needed for? Especially, why is it needed Every. Single. Time?