One little story about having to use cash:
I am currently living in Peru. I rarely ever have to use cash here.
The other day I had to extend my visa. I found the process very interesting. Apparently I would have had to go to the bank even if I were filing my paperwork in person at the migration office.
I had to go to the national bank and purchase a receipt with cash for the amount of the extension fee. Then I came home, and logged onto the migration website and fill out my request. On the last page of the application I had to fill in some numbers from the receipt.
I got my visa extension, but for someone who is so used to just commanding LastPass to fill in my credit card info, it was a unique cultural experience. I did get an impromptu language lesson while waiting in line at the bank.