As far as you formulated your questions in context of submitting an Infopath form specifically to a sharepoint list, I do not believe you have any options except direct submission to a sharepoint list, at least OOTB (out of the box) in Infopath form templates of type/compatibility Sharepoint List Form which is created when you press Customize Form button in browser or Sharepoint List button (< New < File on ribbon) in Infopath Designer. Such forms are rigidly linked to sharepoint list.
IMO, sending a Email (or any other ways of complications) require no less bandwidth and resources than submission of an Infopath form.
So, I would advise to exploit the offline functionality which is enabled by default when you create an Infopath form template (in Infopath Designer).