The journey of Joseph's brothers to Egypt to buy grain marks a fateful and deeply historical moment. It carries the future of the entire nation, even though the travelers themselves are unaware of the consequences of their mission [רש״ר הירש]. Their identity as the Israelites holds a subtle hint for future generations. Just as the brothers are swallowed up by the masses on their way to Egypt, the future nation of Israel will one day be scattered and subjected to exile among the nations of the world [העמק דבר, רש״ר הירש]. Furthermore, the specific group of ten brothers serves as the source for the tradition that any matter of holiness requires the presence of ten men [תורה תמימה].
This moment also highlights the respected status of the brothers. Under normal circumstances, they would not mix with the general population of Canaan. However, the severe famine strikes everyone, including the wealthy and comfortable, forcing the brothers to humble themselves and travel alongside the common crowds. This reality teaches that in times of extreme distress and sheer survival, setting aside one's social standing is not a loss of dignity [העמק דבר, ביאור יש״ר].
The widespread starvation across Canaan sparks a massive movement of people heading to Egypt for food. This mass migration creates crowded roads, allowing the brothers to naturally blend into the heavy traffic [רד״ק, בכור שור, אור החיים]. There are several reasons why they choose to mix into the larger crowd. On a practical level, traveling in large groups provides necessary security against highway robbers, who have become far more active due to the desperate times [ספורנו, ביאור יש״ר].
Beyond basic safety, the brothers intentionally hide their identities. Because they are all exceptionally tall, strong, and handsome, they scatter and blend into the crowd to avoid drawing unwanted attention. Their father Jacob even instructs them to enter the city through different gates to protect themselves from the evil eye [רש״י, חזקוני, צאינה וראינה, משכיל לדוד, ביאור יש״ר]. Additionally, arriving as part of a massive caravan helps them avoid political suspicion. By hiding within the larger group, they hope to avoid being seen as spies [אור החיים]. In fact, the entire nature of their journey naturally argues against any accusation of espionage. They are a peaceful family arriving for a clear commercial purpose, traveling openly within a large crowd, and driven by a crisis that is known to everyone [מלבי״ם].