I feel like this is a parable for A/B testing without considering the consequences.
For McDonald's, straws and stirrers are provided gratis, so you aren't succeeding if you raise demand for the stirrer. If a stirrer sold you more coffee, then it was a success. Just like the thicker straw sold more shakes (some of their competitors never figured that out, and one wonders if they ever actually talked to a customer or just sat in smoky meeting rooms bullshitting all day).
However coffee being a stimulant, there is probably some overlap between the two demographics. It'd be hard to track if a lot of stirrers left with a coffee drinker but were unused for coffee. So perhaps in fact they did sell extra coffee to cocaine users and just patted themselves on the back for the increased revenue.
For McDonald's, straws and stirrers are provided gratis, so you aren't succeeding if you raise demand for the stirrer. If a stirrer sold you more coffee, then it was a success. Just like the thicker straw sold more shakes (some of their competitors never figured that out, and one wonders if they ever actually talked to a customer or just sat in smoky meeting rooms bullshitting all day).
However coffee being a stimulant, there is probably some overlap between the two demographics. It'd be hard to track if a lot of stirrers left with a coffee drinker but were unused for coffee. So perhaps in fact they did sell extra coffee to cocaine users and just patted themselves on the back for the increased revenue.