For me it was mentioned, but I read on HN that the main reason for the "6 month" restriction is that the author wants to avoid complaints and reclaims in the case that he stops providing the website after 6 months. In other words: there are legal reasons why this restriction exists, but it will not be restricted to 6 months. So I trusted the HN crowd and paid the price that I considered as "a little high".
I'd renew for a month to refresh the less usual commands in a heartbeat if it was $2-3 bucks! $25 is hard to swallow.
I do feel like I got my $25 worth at the time though. It was a great way to learn and I use a lot of it daily.
I agree with you, somewhat: there is not much of a server component to this game and we should get to play it forever and ever, and it is frustrating that we didn't know for sure ahead of time this was a 6 months license only.
However, as a solo entrepreneur, I agree even more with the creator of the game. He gets to price his creation however he likes, and he probably needs to make money like the rest of us. His game teaches a super valuable skill that has saved me well over the price in typing efficiency. Again, I'm fine with the price tag. Just wish he had the option to renew for a month after the initial purchase to brush up. Probably leaving money on the table!
Beside that: For every MMOG that was stopped, there was typically lots of fan outcry and attempts to set up fan-managed servers to continue playing (often a legal grayzone). Sometimes fans even manage to convince the developers to release server code/source code: https://en.wikipedia.org/w/index.php?title=Uru:_Ages_Beyond_...
Lesson learned: Don't trust the HN crowd.