The other day I ran across a guy who downvoted an answer of mine that was correct but included an extra paragraph of commentary which he apparently didn't like. I was curious why someone would downvote an answer which they otherwise liked, so I checked out his profile to see if I could understand his reasoning by reading some of his answers and other comments.
He had 1 upvote, 1 downvote, 0 answers, 0 questions, 0 tags, and had only posted 1 comment (the one . He joined 4 days before he downvoted me, and he doesn't seem to have any linked accounts with 200+ rep (the only obvious way I've read about so far which gives you 100 instant rep on one of the other sites without actually doing anything on that site).
I've probably already gotten more upvotes than I deserve for that particular answer, but I'm asking out of curiosity because it seems like this guy just hopped on and started voting right away, when others (including myself) had to answer several questions and begin to get a feel for the community before accumulating the 15 rep required to upvote.
Do you suppose he unlinked his accounts after getting the rep (do you lose your 100 points when you unlink your accounts?), or is there some way to earn 100 points without contributing on any of the Stack/Meta/Super/Server sites? (Or did I miss something else completely obvious?)