yu lot realise HOW cards are cloned dont you ???
they make a copy of the reciept as thats whats got your numbers and expiry, they then look at the back of the card for the 3 numbers claiming to check the signature,,, this is why chip and pin is VERY good as nobody touches your card to get the last three digits,,,,, they dont actually scan the bloody card on a seperate card ready like you see in james bond ect
some places even have lazy staff that loose the pdq slips as they cantbe arsed to manually write the numbers down
at work i refuse to take credit card details over the phone as i used to work with someone who used to take card details on the phone,,, and also use them for online purchases