It's not insane at all, it's how subscriptions
commonly work. They run for the whole year, whether you want the whole year or not. If you can cancel at any time, that's a
feature that is advertised. Adobe also offers this, for an increased monthly price.
When you enter a contract, you need to read the fine print. In this case, you didn't even read the bold print that said it'll cost you money. You have no one to blame but yourself.
> I mean, why stop at 1 year? Why not move free trial users to a 100 year contract with a $10,000 early termination fee?
Because a software subscription running over a period of 100 years would almost certainly be considered an "unfair term" and "unreasonable" under contract law.
Besides that, there are laws governing how products can be advertised, you can't display one price and then hide excessive extra fees in the fine print.
> A certain percentage of users won't read the fine print--easy money!
A certain percentage of users don't read anything at all. There's lots of sleazy companies out there, looking for fools to part from their money. It's usually perfectly legal, because the same laws that make contracts possible make exploitation possible. You can't have one without the other.