In the early days of social media, several people ignored the importance of social media, mostly because they enjoyed much traffic on their own platforms. But check what happens now, almost every reputable organization is on Facebook, Twitter, Instagram, Google Plus and Pinterest. Why the rush?
Social media presence gives businesses and organizations more reach to a wider audience, provide tools for customer service, and take the information you want to pass across to the visitors rather than the visitors coming for it.
Much like the RSS Feed, social media is another source blog posts get to fans, and interested fans most of time return to the blog to find out more about the post. Social media can help with interacting with fans, and would even help you to get to know your fans better.
Social media will increase the worth of a blog, and in turn increase the income. This is how: A 5000/Day Visitor blog with a Facebook page of 1000 Likes is worth less than a 4000/Day Visitor blog with a Facebook page of 10,000 Likes. As long as these Facebook fans are real and are interested in the niche, and your blog sticks to the niche, the Facebook page will eventually provide traffic that will surpass the other blog with less Facebook Likes.
Some businesses would even prefer advertising with a blogger with more social media following, than another whose focus in just on his or her blog.