Comment Been there, done that (Score 1) 486
I worked at an ISP in the midwest and we started doing this as early as late 2001/early 2002. Yes, customers were pissed and we lost some because of it. But as a result we saved alot more time and money then having to deal with abuse complaints, FBI subpoenas, saturated networks, etc.
It is not the ISP's responsibility to protect the customer but it is their responsibility to protect their network. 'If you don't like you can blow me' should be the attitude of the network administrator.