A few times now I've given an answer on a question which was initially well received, but the question has then been locked and my answer has been downvoted (despite being perfectly valid). Equally, all other answers given have also received the same downvotes. I'd understand this behaviour on questions which were closed as duplicates, but this doesn't really work when the question was closed for being too localized, not constructive or not a real question - especially as these are usually determined by the individual rather than being based on fact.
Is there a reason why it's still possible to vote and comment on closed questions (along with making edits and comments)?