People make fake accounts for everything everywhere for all sorts of reasons. Seems as though you stumbled on some fakes that may all be related (all posting starwars quotes) but maybe not. Could be just some off the shelf software that creates twitter accounts.
Probably a non-negligible percent of people with the job description "social media manager" create small armies of bots to do their bidding.
The first stop for any investigative journalist looking into this would have to be blackhatworld.com ... it has a really intimidating name but it's all just about marketing/spamming that violates terms of use.
> "Their potential threats are real and scary due to the sheer size of the botnet," he said.
Kind of overstates things. These accounts will likely be used for spam or advertising of some sort. Journalists have a distorted worldview when it comes to the importance of Twitter. I know you all love it, but the rest of the world doesn't really care.