My local Exxon On The Run offers self-serve soft drinks for 79c up to 44 oz. The catch: they only provide cups up to 32 oz.
I had a 44 oz cup in my car from a visit to a different Exxon On The Run. I used this to get my soft drink. They refused to honor the price. So I told them that if they didn’t honor the posted price, I would pour out my soda. They said it was my choice. So I did.
I don’t understand why they would do this. Once the soda is out of the fountain, it can’t be re-sold. So they turned down my business just to spite me.