Why the cup?


A few days ago, our family splurged and enjoyed a MacDonalds lunch. As usual, we all got water. For us, the big reason is saving $5 or more.

This was the first time I had seen cups specifically for water. Possible reasons for this are:

  1. To keep the customers honest. If another customer saw someone filling their water cup with soda, the fraudulent filler might feel guilty.
  2. To make the water drinker feel self-righteous. They might want to brag that they are drinking a healthier drink than others.

Do you have any additional ideas why they may have done this?