Not sure what screenshot / camera tool it is but either way 5 dollars per month for one trick tool is insanely expensive. I pay 12 euro per month for Photoshop and Lightroom and those can do a quite a bit more.
As I said you can pay one month, get tool for all games that he made it for and canceled subscription. But if tool gets update (sometimes needed when new game patch is released or when he decides to add new feature) after your subscription ended you need to pay again. And for something that I personally won't use that often and doesn't bring me any money it is too much.