Mr. Art Linkletter, tea snob.
Then again, do you want to drink tea that causes your cup to go flaccid? The cup on the left was actually a model where the built-in sparklers went off once too often, causing the cup's structure to weaken.
The ad writer resisted the urge to emulate the name of one of the most popular segments on Linkletter's daytime television variety show: Cups Do the Darndest Things!
Source: Family Circle, April 1958