Well true on currency's local purpose, although that is starting to change a bit with internet.
In this aspect Bitcoin is not very much different from what you get with Visa or MasterCard...
And a lot less hassle too.
BTC currently mainly has a use to do illegal or banned things or just to spend it for the thrill of it. Money transfers are less expensive, but not if you factor the FX losses and price volatility.
Oh one thing is BTC can't be charged back, so that enables some new applications.