When Columbo does his analysis of the two sodas, one is full and the other half full. Columbo then leaves and Bradey returns to the fountain to dump the sodas in the sink. They are now completely empty with only a slight chocolate residue in them. Of particular interest is the fact that it is all one shot, which means the glasses were replaced while Columbo and Bradey are at the door. The originals were likely replaced with breakaway (sugar) glass to avoid possible injury to Fisher Stevens when they shatter.