I'm having a really fun time imagining how a hammer would physically prevent you from hammering a nail based on a subscription.

Handle has retractable spikes (digitally retractable mincers, perhaps?) to promote compliance.

They wouldn't. Instead, they'd try to keep charging you automatically for out-of-plan extra nailing, and if you denied them the ability to charge your CC, they'll put your debt to collections by the end of the month.