Having once been extremely unprofessional to a customer the day I found out my dad had cancer, I can only marvel that the barista managed to come to work, make coffee and give correct chance.

(Two years on my dad is cancer free, and I often wish I could get in touch with that customer and tell her how grateful I am that she understood why I yelled at her once I explained what was going on. Every now and again customers don't suck.)