Re: The poor English reminds me of the 419 scam.
If you don't notice it (or that's how you write and speak generally) you're probably exactly the target mark(et) for these guys.
That thought occurred to me, too, but whereas spammers are perfectly content with having a minuscule response rate someone who wants to influence a democratic election will not be.
I assume that the trolls paid FB and others only based on clicks (and maybe impressions), and they obviously didn't pay zillions to professional marketeers, so the overall expense was negligible in their grand budget scheme of things. If there is any discernible relation to the election at all then I'd say it looks like an experiment that failed miserably.