Italian Neorealism was a post-World War II film movement in Italy. The movement particularly featured impoverished working-class Italians to show the hardships they suffered after the war due to the fall of Benito Mussolini's government, to show life in the fullness of reality. Some of the elements found in Neorealism are poor and lower-class characters, typical daily activities, and child characters who act as observers ("Italian Neorealism"). They were also often filmed in locations in Italy and filmed with natural lighting, both amateur and professional actors, long takes, and open-ended plots ("Italian Neorealism--Main Formal Elements").
One element found in Vittorio De Sica's film Bicycle Thieves that does not strictly fit with Neorealism is a shot of a wealthy family dining on a fancy meal. We see this shot immediately after Antonio is drawn out of the church in pursuit of the thief when he hears someone shouting that a boy is drowning. Since Antonio left his son Bruno by the bridge, Antonio immediately fears it is his son who is drowning and gives up chasing the thief. Antonio is so happy to see that it was not Bruno who was drowning that he takes Bruno out to lunch at a restaurant to celebrate, which is where they see the wealthy family dining. Since Neorealism focused on Italy's poor and lower-working class members of society, this brief contrast between the rich and the poor can be considered a break from traditional Neorealism.
Another element that can be seen as breaking with Neorealism concerns part of the plot. Neorealism focuses on the mundane activities of life, but the plot focuses on a father and son chasing a thief in hopes of regaining the father's stolen bicycle. Several common mundane occurrences certainly do happen in this film: (1) a father's struggle to find work; (2) the need to pawn something of value to redeem something for work like a pawned bicycle; and (3) a bike being stolen. However, what's uncommon is someone actually walking all over town in search of his/her bike as Antonio and Bruno did. Therefore, since this point of the plot is not a mundane occurrence, we can say that this point also diverges from Neorealism elements.