no you will need to have an origin + battlelog account to play online on any legit server, however you may be able to direct connect to a server if there is some file to launch MP in the file path, it would have to be cracked of course and i haven't heard of any as of yet.
i suggest you buy the game as they will continue to keep the game updated and release expansions for the rest of 2012 and 2013.
And of course i dont know many people who would get bf3 for the single player, its notorious for being terrible.
Good Luck anyway