People can't/don't t read URLs and GET is largely to blame.
This "fact" was discovered when a popular blog post on the topic of Facebook login reached #1 on Google.
Angry comments soon filtered in about people not being able to log in and why did Facebook change the site and how the old one was much better.
Turned out many had no idea what the mumbo jumb in the location bar was and had developed a habit of totally ignoring it. To log in to Facebook, they went via "Facebook login" on Google and got accustomed to clicking the top result.
Segments open up URLs to become more readable, comprehensible and usable.
