From Monkey Island wiki
The Gum Machine is a vending machine that only appears in The Curse of Monkey Island in the Voodoo Lady's house on Plunder Island. Guybrush uses it to obtain some gum which will be useful in obtaining Captain Blondebeard's golden tooth. It dispenses a package of gum at the cost of a wooden nickel.
- This is the only game where this machine appears. It is also the only game not to feature the Grog Machine.