What they benefit from doing this I don't exactly know, but I've found several threads made by these 1 post newbies which are either completely copy, and pasting or are only using a snippet of the text from another source. They seem to be getting a lot of it from news websites, but are also copying from much earlier posts on this forum too.
One possible guess would be a random dude having a myriad of accounts,and he sacrifices a few of those by plagiarizing topics,and using his other accounts to spam their way through. All this for bounties maybe. Cases like this have been true before,people managed to get hell a lot of rich.
Instead of totally abandoning Bitcoin Discussion, maybe just keep having discussions with those who want to. Create your own self moderated thread,and discuss stuff. We all came here to discuss about bitcoin and we are doing everything else other than that.