What does Genesis 37:25 mean?

After that, they sat down to eat. While they were eating, they saw a group of traders coming from Gilead. Their camels were loaded with spices, balm, and resin, and they were on their way to Egypt. Genesis 37:25 - Modern Text Bible

(The brothers are so callous that they eat right after betraying Joseph. The arrival of the traders sets up the next step in Joseph’s story.)