Same goes for Emacs, nobody points you to the Info system, which is absolutely amazing.
Perhaps this is because both vimtutor and the Emacs tutor do refer to their respective help systems, but given the sad state of most help systems beginners are familiar with I think they can be forgiven for not taking the recomendation seriously. Its worth really emphasizing to beginners that there is a follow up to the simple vimtutor/TUTORIAL built right into the editor.