Bit.ly could have just stopped redirecting your urls, waited for you to figure out why and contact them. They didn't do that. They contacted you and gave you a

Bit.ly could have just stopped redirecting your urls, waited for you to figure out why and contact them. They didn't do that. They contacted you and gave you a chance to fix what you are doing wrong. Plus they probably could bill you for past traffic but they aren't doing that either.