Final answer:
The writer aims to create interest by setting up a challenging scenario that disrupts the family's plans and captures the reader's curiosity about the consequences of bringing unexpected guests.
Step-by-step explanation:
The writer begins the story with a family running late to their grandfather's house and bringing five more people than expected in order to create interest in the story. This opening sets up the situation that challenges the family and has the potential to disrupt plans, thereby hooking the reader's curiosity about the consequences of these unexpected developments. The writer doesn't seem to be aiming for humor with a ridiculous situation, or giving much thought to detailing the dinner or the grandfather's reaction at this point. Instead, the focus is on the dilemma that the family faces, which becomes a driving force for the narrative.