Fellow Brazilian here and I don't carry a lot of cash with me because that was how I was raised, mostly my parents taught me to be scared of being robbed with a lot of money. Even though I am not living in Brazil ATM I still act like this.

Plus fraud is becoming rarer with chip credit cards(and apps which allow you to lock your card much faster in the case of theft), while counterfeit bills are also harder to reproduce these days you can still find some.