I've use bitcoin to buy computers, gold, silver, and various collectibles on this forum. It is very useful if you know how to spend it.
It is true that we can not use bitcoin for everyday transactions in everyday life. But you are right we can buy high value stuff from bitcoin, bitcoin is very useful.
Yes, bitcoin is very useful in digital exchange and trading transactions, but for me I would rather cash-out some of my bitcoin and spent paper money in real life in order to avoid hustle in every transaction we encounter.