Examples:

• She said we have the tools, why not use them?
• If the Queen gives her permission, then why not?
• You have the box, why not just let us go?
• If you have to marry someone, why not the doctor?
• Actually I have a car, but yeah, why not?
• So why not take advantage of his special mercy?
• So why not use one problem to solve the other?
• But why not take a ship to get to Ethiopia?