If a site closes or a script is no longer supported and stops working which you purchased you can decode it to fix it for personal use under the terms you were previously using it as long as it wasn't a subscription based model.

It's an example and I'm not saying it happens often but you can't penalize legit cases no matter how few they are because of a some are doing it for illegal purposes. That would be like the government banning everyone from driving a car because a few people speed. You don't penalize everyone. You punish the people who commit the crime.

The easy way is to punish everyone but it's not the fair way.