A lot of people only have debit cards in Australia, and consumer protection is a lot stronger than the USA. Most credit cards in Australia have an annual fee, and the only rewards are usually frequent flyer points, so they’re nowhere near as common as in the USA.
I’m Aussie but I’ve been living in the USA for 10 years. American credit cards are something else. So many good cards with no annual fee, great perks (like extended warranty), and great rewards (like cash back, or points that are worth way more than in Australia).