Why couldn't they simply allow initial setup without the phone-home, then recommend a user-initiated phone-home for updates only (or request to continue auto-up

Why couldn't they simply allow initial setup without the phone-home, then recommend a user-initiated phone-home for updates only (or request to continue auto-updates, etc.)? If I stop receiving security updates, at least I could use the devices in an isolated network, or through a separate firewall/controller, whereas the former case is just a paperweight.