Cashiers: How would you like me to tell you I ain't giving you my phone number?

Exactly right. If you can show that the signature is forged, the merchant becomes responsible for the fraud. It is their job to check the signature, even if they don’t.

I don’t think I’m allowed to refuse payment with a credit card because of the signature. I don’t know why they bother.

I like to give the number of someone that drives me nuts. That way, telemarketers can drive this person insane in their spare time.