Trivia: Macaulay Culkin reprised his role as Kevin McAllister in 2018, recreating key scenes in the film in an advert for Google Home.
Trivia: When Kevin is in Buzz's bedroom, he finds in the box a picture of Buzz's girlfriend. This is actually a picture of the art director's son dressed up to look like a girl, because the director, Chris Columbus, thought it would be too harsh to make fun of a girl like that.
Trivia: Kevin's line "You guys give up, or are you thirsty for more?" was improvised.
Trivia: The infamous black and white movie was called "Angels with Filthy Souls." In "Home Alone 2," it was called "Angels with Filthier Souls" - it was a sequel, as was Home Alone 2.
Trivia: Catherine O'Hara has said that Macaulay Culkin still calls her Mom, even 25 years later.
Trivia: The boy that plays Kevin's cousin Fuller is Macaulay Culkin's brother, Kieran.
Trivia: Macaulay Culkin was only allowed to work for 5 hours a day and so his scenes had to be carefully planned around his schedule, for example he was often filmed alone while other actors' shots could be added to the scene later.
Trivia: There is a scene where Kevin is walking past a driveway just as Harry and Marv are driving down it, and they stop just in time to avoid hitting him. This was achieved by having Macaulay Culkin walk backwards, as the van was driven in reverse away from him; the film was then shown backwards. It's hard to tell - but if you look at the smoke from the exhaust, it's drifting toward the van rather than away from it. (00:42:15)
Trivia: Christopher Columbus keeps Kevin's sled in his office - it has been signed by all the cast.
Trivia: The railroad tracks that Kevin crosses are in Winnetka, Ill. behind Hubbard Woods Metra Station. Right across the street is the drug store that Kevin steals the toothbrush from.
Trivia: When Marv grabs Kevin, Kevin grabs his tarantula spider and puts it on Marv, who then screams. Daniel Stern had to mime his scream because the noise would have scared the spider, and the scream was dubbed in later.
Trivia: During the scene where Harry bites Kevin's finger, Joe Pesci actually bit Macaulay Culkin, leaving him with a scar on his finger.
Trivia: A small in stature adult man, who was 20 years older than Macaulay Culkin, was used as his stunt double.
Trivia: Marv's lines "Why the hell are you dressed like a chicken?" and "Maybe he committed suicide," weren't actual parts of the film - they were improvised.
Trivia: Despite playing siblings of different random ages, the four actors playing Kevin's brothers and sisters were all the exact same age (all born in 1977).
Trivia: In the IO Interactive video game "Hitman", there's a side bonus mission called "Holiday Hoarders" where your mission is to take out two thieves named Harry and Marv. In the intel, both men are from Chicago and after several break-ins that went wrong, the two flee to Paris. Harry is said to have a history of breaking into mansions with security equipment way beyond his capabilities to overcome.
Answer: I think it was a way to make leaving him "home alone" more realistic and understandable as opposed to absurd. Being perceived as a brat/pest and annoying to be around, it is (somewhat) conceivable that none of the family members would be eager to have Kevin by their side. This "frees" all of them from noticing that Kevin isn't with them. Everyone would just assume that Kevin is somewhere among them and each be glad they didn't have to sit next to him on the way to the airport or during the long flight.
KeyZOid
In addition to this, the movie is partially about Kevin learning to have more respect for others. He appreciates his family more as he spends more time without them.