When you buy SP you buy influence, and on Steemit influence is king. When you’re sitting on a fat stack of SP you have a lot of options that most other minnows do not. For a start you can upvote your own post (GASP!!! I know you’re not supposed to do this right?) You also find, all of a sudden, that other minnows want to know you. They don’t really want you, but they want your upvote, so they do things like vote for your posts and comment on them as well, in the hope that you will return the favour. So, suddenly you find your following grows.
This is a demonstration of an element that amplifies the Pareto distribution. Think of it as "the snowball effect".