I have Australian and Thai debit cards. I only use them for emergencies in Thailand, as getting skimmed is apparently a constant risk. Lose a card, it's a nightmare getting it stopped and replaced. Lose a few hundred baht to a pickpocket, mai bpen rai.
As I partly live in a village, and also buy food in the day markets, cash is more practical. Yet to see a street vendor armed with an EFTPOS terminal.
Payment by phone is the new frontier in Thailand, to me that is even more of a security risk.
In Australia, different story. I use a debit card for everything, can't remember the last time I paid in cash.