Exchange it man. Don't settle.
I agree, when I buy a tool or anything else for that matter,I expect it to be right unless I know ahead of time (scratch and dent,blems,etc.) Besides if the head of the hammer had enough slop in it to be mounted any other way but straight on,then you may be asking for problems on down the road. A hammer head flying off the handle and hitting you in the head isn't a pleasant experience (don't ask me how I know lol)