For a number of bay area devs I suspect this might have the opposite psychological effect. A $50 price tag might put some people off until they realize it's only 15-20 minutes of work.
Yeah this is exactly what I was thinking. I am certainly more put off by $50 than N minutes.
On the other hand I often base my purchases based on "Will this $50 spend save more than N minutes of my time"
For example a top-filling humidifer may cost $50 more than a bottom-filling one but I spend an extra 1 minute fighting with the bottom-filling one and cleaning up water spills so after 15 uses it makes up its price difference.
The extension also shows you a random but helpful prompt to reflect on the nature of consumerism and happiness. Maybe it won't help everyone, but I hope that it reaches some.