I currently don't have plans to give out Steam keys with one's itch purchase. The game is DRM free on itch, and will always be updated to the latest version, just like on Steam. I do understand that some people, perhaps like yourself, would like to have all their games in one place (currently mostly in Steam), but I would like to see itch become that kind of place as well. And to keep giving out Steam keys wouldn't contribute to that fact.