I sympathize with the barista here, but mindset that customers need to cover 10 to 20% of his income is symptom of decades of brainwashing of employees and customers alike. In this case NPR is part of this brainwashing. I will not tip someone for doing their job. I will only tip when I feel it is needed based on the service provided.
I mean, it IS. Restaurants need to price their menus so that everything is covered in the price I HAVE to pay. That includes a liveable wage for the employees. Whatever I give on top is up to me and a small gesture of gratitude if the employee is exceeding my expectations.
What I give on top shouldn’t be there to pay the liveable wage. It should actually be on top of that. You know, what a tip was originally meant to be.