All of our online credit transactions go thru a secured credit card payment gateway i.e. Eway which is PCI DSS compliant. We do not store any of the personal credit card details during these transactions.
Credit cards can be compromised thru many other methods such as physical card skimming, contactless recording, modified EFTPOS/ATM machine, or malware related hacks.
Just a note, we have had zero other complaints of this nature from our many tens of thousands of customers. We're sorry to hear that your credit card was indeed compromised.
Scorptec Web Development Team