a guy shot for stealing?

Occurrences like this aren't unheard of in many third world/impoverished nations-- especially in certain parts of Latin America where there's a lack of sufficient law enforcement or the law enforcement themselves are corrupt. There's an "every man for themselves" attitude. You also have to consider that something like a toy (while trivial to us) is a source of income for the vendor. In a country where survival is dependent on something so seemingly simple, there's very little tolerance for theft, etc.

It's for show that's no other way for Josué than the one presented in the plot.

Brazillian working class have a very low tolerance for pety theft. I still remember news, some years ago about an old lady who shot a young thief to death in a bus. When the driver tried to hold her for the autorities, the other passengers beat him bloody.

An incident like this actually happened in Brazil, and the directors wanted to remind people that such horrible things were happening in their country.