Other mistake: In the 15th minute, in the scene where the two gangsters first spot Michael Douglas, one is smoking a cigarette and smokes it backwards. The tan filter is visible on the end of the cigarette.
Other mistake: From the front, D-fens' ex-wife's home is shown as being one house left of the beach. When the officers are in the back of the house, there are neighbors living to the right of the house, where the beach should be. (01:30:20 - 01:37:05)
Chosen answer: Because the beggar thought there would be items of value in the briefcase and he was frustrated that there was nothing in there. So in frustration he threw the apple at D-Fens.
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