Charles Spurgeon Commentary Acts 27:37-39

"And we were in all in the ship two hundred threescore and sixteen souls. And when they had eaten enough, they lightened the ship, throwing out the wheat into the sea. And when it was day, they knew not the land: but they perceived a certain bay with a beach, and they took counsel whether they could drive the ship upon it." — Acts 27:37-39 (ASV)

They wanted to let it go ashore, and break up, and so save their lives.