I help run a fairly large email newsletter. Recently we have discovered that our click through rates have been artificially raised by some kind of bot activity. They are clicking on links in our emails a couple hundred times. I've looked up the email addresses that they use to sign up and they are using the same email addresses to join a couple of other sites. How could they benefit from clicking on links in our email, or is it just a side effect of some other activity they are doing?
The newsletter contains celebrity and shopping information if that helps.