This is a very bad step. If they activate the refund mechanism, then there will be no difference between Bitpay and Paypal. People are going to misuse it, to cheat honest traders.
Please read the article thoroughly. This has nothing to do with the so hated charge backs from PayPal. This is about underpaid transactions and overpaid transactions. Instead of contacting the merchant and BitPay, you can now add an address where you would like to receive the change back. Or in case you underpaid a transaction, it will be returned to you. That's it.