Incredibly, people never expect to get hit with a snowball in the house

Incredibly, people never expect to get hit with a snowball in the house

My daughter recently brought a snowball into the house, which is why I chose this statement to consider. It is a joke from Calvin and Hobbes.

The humor in this joke lies in the fact that Calvin finds it hard or impossible to believe that people wouldn't expect to get hit by a snowball in the house. Calvin has been shown (in that comic) to not have a normal person's understanding of what is socially acceptable.

The reason why most people do not expect to be hit with a snowball in the house is that there is an unspoken social contract about throwing snowballs in the house. It causes so much of a mess, that people just wouldn't do it, however Calvin never considers that.

The humor of this joke is, therefore the fact that Calvin is ignorant (willfully or not) of the reasons why people don't expect to get hit by a snowball in the house.