The time argument might be relevant, but even then, most Brazilians do have cheap and easy access to a very healthy lunch in restaurants or to-go meals, purchased or prepared, with rice, beans, meat, salad... The breakfast is probably bread, but I'd say most people don't eat a lot of that in the morning. Getting proper nutrition at night will probably be problematic, but it's also a smaller window...

But, like I said, processed food is quite expensive here. For instance, a 1 kg of chicken breast goes by less than a third the price of a McDonald's combo. A pack of cookies or snacks will be like double the price of a 1 kg of bananas...