One thing that really stands out about Australia is that tech startups here last a long time (they don't seem to ever 'run out of money'). Investors are patient and they invest cautiously; in fact, if they like your idea, they will 'keep tabs' on you and they won't invest a single dollar until you have some meaningful numbers to show them - And by numbers that means either decent revenue (yes, REVENUE) or exceptional user growth (coupled with a clear monetization plan).
That's both good and bad. It means it's very difficult for early starters to get funding in Australia, but it means that once you do get that funding, you can expect the investor to stick around. I have worked for 2 startups which had been operating on a modest loss for 5+ years - One of them had almost no growth and little potential (in my opinion), the other had modest growth but high potential. These startups don't seem to have problems raising further rounds of capital year after year.
I found that Australian startups are lean and have a low marketing budget - They tend to spend everything on the product and generally don't like hiring sales people or paying for advertising unless it gives them an immediate, measurable return - They don't spend money just to create hype.
Australian founders tend to dismiss the importance of advertising - They believe that if they put all the focus on product development, that eventually, the product will become so good that it will just blow away the competition (who have wasted all of their funding on advertising).
US startups generate a massive amount of noise in the market - Spending on advertising at the moment would just create more white-noise - You won't get a return on that. At least that's the general belief.