It is interesting. To make it more convincing, it needs to take time into the equation. Making your own laundry detergent vs. buying tide. Do you have spend 15 minutes on it? If you make $10 per hour, then it is no big deal. But if you make $100 per hour, 15 minutes can make an impact.
Of course, you can also add environmental effects into the equation. Anyway, this is an interest but incomplete article