1. Weddings were often accompanied by celebrations and gifts.
Perseus steals the eyeball when he finds the Gray women, in exchange for the Nymphs of the North location. Perseus travels there with the help of Hermes and finds the happy people's land, who are always celebrating and banqueting. Therefore, they gifted him a magic wallet that could change its size, winged sandals, and magic cap, that turn invisible to a person who wears it.
Another instance which highlights ancient Greek life is when Polydectes called his friends including Perseus for his marriage celebration. At the wedding, each guest as a "customary" got gifts for the bride.
"He announced that he was about to be married, and he called his friends together for a celebration, including Perseus in the invitation. Each guest, as was customary, brought a gift for the bride-to-be, except Perseus alone."
2. Fishing was one way coastal and island dwellers made a living.
"This radiant personage [Hermes] told [Perseus] that before he attacked Medusa he must first be properly equipped, and that what he needed was in the possession of the nymphs of the North. To find the nymphs' abode, they must go to the Gray Women who alone could tell them the way."
"Fate willed it—or perhaps Zeus, who up to now had done little for his love and his child—that they should be discovered by a good man, a fisherman named Dictys. He came upon the great box and broke it open and took the pitiful cargo home to his wife who was as kind as he. They had no children and they cared for Danaë and Perseus as if they were their own."