Gum and sweets occupy a different semantic space in Brazilian culture than they do in American culture, as might be expected. Just to give one example, Halls, which seem to me as a native informant of American culture to be mainly things we grudgingly buy when sick because we want to breathe, in Brazil are basically breath freshener/candies. There are many flavors that don't even have menthol.
The girl in the photo seems to be pointing to the Dori raisin or peanut snack (the yellow package), or possibly the Freshen-Up gum next to it. That would be a surprising choice, though, since it seems to be marketed more to adults who are worried about their breath (the refreshing gel center sets the germs running, I guess).
The number of small vendors like this in Rio Branco is very large. Most corners have someone selling little mouth-toys like these, sometimes cigarettes. Their carts close neatly up and uniformly have wheels to take them away; some are even built around a bicycle so they can be ridden away.
Surely some are registered, but the size of the informal economy is also very large. Most Sundays, for example, some lady takes over the bus stop we use most often to sell her baked goods and coffee to passers-by. And on any given night, between here and the park down the hill we'll encounter three or four folks selling sidewalk bbq skewers for fifty cents or a dollar, cooking them often in converted auto wheels. I am sure none of these folks have permits.
And enforcement of licensing is sparse. Heck, some guy who built a 15-foot brick smokestack in the middle of the sidewalk had it there for a few months before the city made him tear it down.