I'm not sure if politeness is the motivator. Imagine if you had done that, for all hotlinks to your script. Then, it turns out a children's website is hotlinking your script.
Some idiot at Company X decides that it's actually your fault, since its your script that did it. To save face, they get an expensive lawyer to sue you. Next thing you know, you're a registered sex offender.
Some idiot at Company X decides that it's actually your fault, since its your script that did it. To save face, they get an expensive lawyer to sue you. Next thing you know, you're a registered sex offender.