Do moderators have the privilege to accept the answer on their own if answer gets much positive points and is helpful for users?
No. Only the question's author can accept an answer.
Oh, thanks for answer! :) Jan 18, 2014 at 15:06
But especially unregistered users tend to not accept an answer, and they will wander around like a ghost in the system :( Community (-1 user) will push them to first page every now and then, users look at the question again and again, but the answer has already been given. Would be nice if a moderator could accept an answer after like 2-3 months, or community vote after this time.– CodeManXFeb 17, 2014 at 11:37
1@CoDEmanX, as long as at least one answer is upvoted, Community will not bump the question. The criteria for bumping is that both must be true: A) no upvoted answer, B) answer not accepted. May 29, 2014 at 12:15