Kevin’s ticket wound up in the trash after the milk got spilled all over the pizzas. That snotnosed neighbor kid who unwound a yo-yo while going through people’s bags got counted instead of Kevin. Buzz was being a dickhead and trying to throw the headcount off while everyone was in a rush since they all slept in.

The real question is if the McCallister family had mob ties since the whole family(including Kevin who didn’t go but was accounted for) went on two nice vacations two years in a row. They lived in a ritzy suburb of Chicago in a house with two staircases and three floors. His mom was likely a fashion or costume designer which explains the mannequins in the basement that he used to make it look like the house was hosting a party. His dad’s occupation is nebulous at best. There were no awards or other marks of achievement to be seen in the house of a seemingly accomplished businessman. The pizza guy heard a tommygun going off and didn’t report it to the authorities. He probably didn’t want stitches.

The vacant brownstone owned by his dad’s brother in 2 recently sold for 6.7 million dollars in today money. The book apparently says he is some kind of prominent businessman. I don’t think the explanation from the book rules out mob ties though.