In Treasure Island, why doesn't the captain just leave when Silver and most of his men have their day of leave on the island?

The classic adventure novel Treasure Island by Robert Louis Stevenson tells of an exciting search for pirate treasure. Jim Hawkins first finds the treasure map when a pirate named Billy Bones visits the Admiral Benbow Inn, which is owned by his parents. Hawkins, Squire Trelawney, Doctor Livesey, Captain Smollett, and a crew of sailors set sail for the deserted island on which the treasure is hidden. However, on the way to the island, Hawkins, while hiding in an apple barrel, overhears the pirates plotting mutiny. He informs the loyal passengers so that by the time they reach the island, they are aware of the pirates' plan.
There are several reasons why the captain does not leave when Silver and his men go ashore. First of all, the squire, the doctor, and the captain are still determined to recover the treasure. The captain makes this clear in chapter 12, "The Council of War," which takes place after they have discovered Long John Silver's plot. Additionally, Silver leaves enough mutineers aboard the ship that the loyal men will not be able to fight them and take it back. The other reason is that Jim Hawkins stows away in one of the boats going ashore so that if the captain sailed away from the island, he would be leaving Hawkins behind with the pirates.