GP is actually correct. I have handled hundreds of chargebacks for a brick & mortar store...
Here is the exact process:
1) Consumer goes to B&M store, makes purchase, signs receipt.
2) Consumer issues chargeback.
3) Bank sends notice to merchant.
4) IF Merchant fails to respond in 30 days, judgement is automatic against Merchant and the charge is reversed
5) IF Merchant responds with signed reciept, video footage, testimony from the cashier, or other evidence that the consumer DID make that transaction, then there is a small chance that the bank will let the charge stand. Most of the time, the charges are reversed anyways. But, most of the time it is fraud, and most people are honest about chargebacks.
The burden is absolutely on the merchant to prove the identity of the customer. Checking an ID doesn't mean squat to the bank. Making a physical imprint doesn't mean anything. Physical imprints are considered Keyed rather than Swiped, so you get charged a higher fee per transaction (because of higher fraud costs). There are no sure-fire methods to protect the merchant.
My company processes millions of card transactions per year. We ignore most chargebacks, because it is a waste of time to fight the bank, and probably was a cashier that didn't check ID. 2% of the time, they will let the charge stand as is and charge the consumer. 98% of the time they take the money from the merchant and give it back to the consumer. The bank does not ever eat that cost. PCI has nothing to do with it. Despite all this, it isn't cost effective to upgrade equipment outside of our normal cycle. We could potentially save 100% of chargeback fees, but that would still take years to pay for the hardware, since we have an overall low fraud rate.
One more aside, EMV is not required to be PCI compliant, and isn't part of the future standard. PCI compliance WILL still be necessary in the future, because card information WILL still be stored locally by the merchant.