It's easily to promote your fan page on huge friend list It's useful if your page fit on their interested
huge friend list can draw traffic in your site. when you share some contents of your site, or some videos in your profile, then many people will go to your site and read or watch your contents. some of them may become your regular visitor. so it is always good to have a huge friend from different corner of the world. thanks
A huge friends list helps in that it can get you to other people's news feeds if your friends decide to share, like, comment, etc on anything on your page.