There may be a way to get a free beverage.
Some people enjoy having free stuff, especially drinks. If you are one of those. there is a trick that you can follow, but it only works for people who are nonalcoholic. If the meal has been served and you have already ordered drinks with your meal; wait for the meal to be over then order some cheap soda or a not-so-expensive drink.
It’s more likely that the servant won’t bother charging it to your bill, especially when you have already paid for other beverages because mostly the restaurant is too busy and the server doesn’t seem to care to add that cheap beverage to your bill. So here is your free beverage!