I think I’ve misread something then. Sorry about that. Maybe Envato just wanted the authors to use this – http://notes.envato.com/general/envato-wordpress-toolkit/
As far as I know, they don’t like this or maybe it wasn’t allowed in the past, I am not quite sure. But most of the authors use some kind of external updater for the speed reason.
If you are not 100% copying and pasting from the tutorial, but making it unique to your theme/template, then I see no flaws here.