Dev has said keys for Itch won't be coming on the Discord server. From the FAQ section:
"Can I get it on other platforms if I bought it somewhere?
You can download the android version if you bought it on itch. That is all."
It's just a ploy to sell to the same players again and again. You might not want to call it what it is, but it's scummy behavior. And sure, there's no obligation to do it as it wasn't ever promised, but that doesn't make it right... The honorable thing is to just make it easy for the early players/supporters.