Why didn't the Boy immediately turn over the "loot" the next time he saw his father when he did this all for him?

He obviously didnt do it for the $5 he spent on candy. He probably assumed his dad would let him get candy. But why did he wait? (except for the filmakers dramatic effect)

I immediately knew as a viewer that the goat would get into that bag, but what didnt make sense is the boy's delay let that actually happen. I'd assume he'd be thrilled to let his dad know he found the "loot" and be the hero of this story. ( I then assumed his dad would ave told him its not it but that's beside the point). The film did a terrible job of having the boy act irrationally with no reason to do so (other then to continue its narrative ) of the father having a melt down as he was never a father figure to his own children.
However in the fathers mind this all had to be linked to his anger of not finding what he was after and the Boy clearly knew that.

This is one of the main reasons I think this movie did a very poor job. I rate it a 3.5/10

If the boy had given the dad the "loot" there would have been more time for the father to get closure and move on with his life with that the viewer ultimately wanted. For him to actually be a good father.