Because it's a commodity. The difference? You can't just print more commodity, if you need to, like you do with fiat currencies. There is a fixed supply limit. And in that aspect bitcoin can never be a currency.

'Yet' was just me being hopeful for the future, as in: hope for more widespread adoption (merchants, merchants, merchants..), maybe official recognition by the governments? etc.

Hope I haven't spouted too much nonsense/BS, I'm still kind of new to this whole economy/money thing ;)