The No ICE in Minnesota bundle had the Steam keys icon showing how many Steam keys there were in this bundle (16 or 17 keys at the time). This has since been removed but it doesn't change the fact that at the time of purchase this was included. At the time of purchase an agreement was made that isn't being honored. I'm all for the cause but this is very likely illegal and poorly handled.
Viewing post in cant find my steam keys anywhere???
Interesting question. It seems that this is not quite straight forward. The actual contract formed for such a transaction is complicated. You actually do not seem to buy or form a contract, when clicking the buy button, but at a later point.
I think the answer might be, how it is handled, if you buy a game regularly, that had Steam keys available, but then the devloper disables the external keys. External keys are an optional bonus and not actually what was bought. Itch even points out, that you cannot normally have a project that only sells an external key. And those keys have to be manually added by the developer and can run out. They are only seen as an alternative way of distribution, just like you could upload a game to a file hoster and after buying you get the download link to the file hoster.
I do not think there is a legal case here, seeing how the Steam keys were not advertised before you clicked buy to encourage you to click there in the first place. But if you bought during the period where there was that display issue with the summary of how many Steam keys there would be, you might be eglible for a refund.
But honestly, who refunds a donation to a charity. All the content bought is available, just not on the bonus option that a few games have.
I wonder if they only displayed it in error, or if they forgot to disable the external keys and some people grabbed the availbable keys till they run out.