About facebook like sites (many domains with the same content)

Hello,

I have a question.. I see one fan page that he share like quotes from websites.. I checked some of the links and i realized that all the domains are the same like script with the same like posts..

For example 1.shareit.com, likemeornot.com, 126465.likesoup.net and something domains and weird subdomains like that. It seems random domains lol

Is there any reason to do this? Or he made it to have backups?

(I dont post the exact domains here for obvious reasons )