Retrieving pages via ajax... what's the purpose?

[erdubya]

I was recently looking on the site http://www.amylacour.com/ and saw it rather odd that the website retrieves pages via ajax/javascript all while keeping the amylacour.com website in the address bar.

I thought it was odd and bad for SEO among many other things.

Am I missing something? Or is there a reason why a web designer created the site like this? How is coding this site this way advantageous?

[rnd me]

it provides a smoother user experience.

you don't have to restart word to open a new document, why should you have to reload a page?

can you image a refresh laden gmail or google maps experience? yuck!