When you include the hosting service, having a subscription (since you're providing an ongoing service) makes perfect sense. In this case, so does also forcing the current version.
I agree that subscriptions make perfect sense for services (because servers, support, etc. cost money on a monthly basis), but the trend seems to be to create an arbitrary reliance on a hosted service as a way to justify subscriptions. Luckily 1Password hasn't totally gone that way yet, since they still offer standalone licenses for local vaults, but I feel like it's the direction they're going.
