In the list of mathSE users by number of votes in the last quarter, there are a few examples of users with little to no reputation gain or site activity, but a lot of votes. Specifically:
A user has 101 reputation, no questions, and no answers, but voted 2443 times in the last quarter.
A user has 398 reputation, 19 questions, and 5 answers, but voted 719 times in the last quarter.
I think the "last quarter" includes July, August, and September.
Is this (particularly the first bullet point example) suspicious behavior that should be reported to the mods? Everyone like upvotes, and these users are throwing a lot of votes around. But it also seems that this ghost behavior (casting so many votes but remaining invisible) may be questionable for the following reasons:
The user could have some bot or some script installed.
The user could be attempting to game the system to get badges (Civic Duty and/or Electorate).
Even if the user's voting is genuine, perhaps their voting is uninformed, mostly only voting on popular questions, or otherwise not helpful to the site. (Especially considering, if their reputation is under 125, they cannot downvote, so all the votes are upvotes.)
So, I'm looking for community and/or moderator feedback as to (i) whether this is undesirable behavior and (ii) what, if anything should be done about this.
I'm tagging this
(specific-user) but the question is really about this sort of behavior in general, not any particular case.