Well, it is. So don't be wasting water unnecessarily. If you spent time and money eating at McDonald's why would you throw it away? Our society wastes a lot for sure so try not to. Don't go to McDonald's in the first place.

We don't have a water shortage problem just like we don't have a food shortage problem. We have a water/food distribution problem. Throwing away a burger in the US takes nothing away from Africa.

If you bought this burger, you already gave back to society by paying for it. It has zero influence on the rest of the society whether it goes through your belly or not before being disposed.