This site is another example of the new trend in longer websites. The purpose of these types of sites is because of the "engagement" factor that Google is looking for in a website. Google wants to see people engage in your site.
Engagement includes activities such as clicking on links on a website, spending time browsing pages or simply spending more time on a site, and scrolling down a page. When a website has longer pages, a visitor is forced to scroll down the page. This automatically satisfies one of the engagement factors which Google is looking for.