content: Yes, there are times when things are cash only.  Small county fairs sometimes are cash only.  There are other events as well that only deal in cash because its the quickest transaction method and they want to keep people moving.  Also, a ton of small things like buying your neighbors law mower, or going to garage/rummage sales.  All this stuff is cash.  I don't see cash ever being eliminated, and if it is, alternate cash currencies will pop up in its place.