Good point, however, I'm not sure I can recall a time during which someone intended to collect a URL from me but allowed just "example.com" as a valid input. I

Good point, however, I'm not sure I can recall a time during which someone intended to collect a URL from me but allowed just "example.com" as a valid input. I'd venture to guess that the validation enforced more often than not actually helps the site owner achieve their intended goal.