Do not make someone buy peace by paying for something they did not choose.

Group spending has a way of settling on the person least willing to argue. Someone orders the expensive bottle, books the larger place, upgrades the plan, and then the total is split evenly and the quieter person pays rather than make a scene. That is not agreement. It is the price of avoiding an uncomfortable minute.

When you are the one proposing the cost, say the number before it becomes binding, and make it genuinely easy to opt out. When you are the one splitting a bill, ask rather than assume. And if you were the quiet one last time, you are allowed to speak first this time.