Just because you revoke payment doesn’t mean you cancelled (at least in Europe). If you just stop paying, they will sue you to get the money.

Yep, in the US you can have the debt sent to collections.

My spouse got fucked by Shutterstock and we have to have a calendar reminder to cancel this when the year is up, since cancelation prior will result in us still paying out the year, but not getting the remainder of the service.

They're extremely scummy. I could certainly block the charges, but they'd just come after us and cause a headache.