Visible crew/equipment: When Tom and Dylan are hanging from the chandelier, there is a shot of the ceiling showing the chandelier coming loose. Then when it cuts back to Tom hanging from the chandelier, in the background behind him is a crewmember holding a boom mic. (00:24:15)
Visible crew/equipment: When the kids are being punished by Tom for soaking Hank's underwear in meat, you can see a bit of the microphone from the overhead shot at the top of the screen. (DVD)
Visible crew/equipment: When they find Mark at the train station in Midland his mother gives him a hug, and a crew member's shadow is visible on Jake Baker's T-shirt.
Visible crew/equipment: When Mark goes back to his bedroom, after the fight with his family, you can see a crew member reflected on the door before he enters the room.
Answer: It seems that the fact the family can't take care of themselves is added to part of the humour of the film. 12 children is a lot, and think about all those rows and all that mess.
Hamster ★
It's not like they couldn't take care of themselves. As shown with the breakfast scene at the beginning, they seem to function pretty well when they all get along. Tom and Kate were just usually home more frequently than some other parents. It also didn't help that it was the first time that one of the parents was gone for an extended period and the parent that was left home (Tom) had never had to deal with all the kids on his own. Also, the only time we see complete chaos in the house is the first day that Kate has been gone. After that the kids are more behaved (at home).