I think that Bitcoin can be both a currency and a commodity during its growth phase. You can use it to buy coffee as long as you replace those coins at the end of the day. For the most part though, Bitcoin will be pumped up in these early stages by investors.
Well yes, and in later phases too (I envisage using BTC to buy PMs in the future, for example). The point is that using BTC as mere currency, and encouraging others to think of BTC as something they can buy groceries/coffee/beer with, doesn't really help Bitcoin. (And, taking this further, could potentially be detrimental - if someone buys 1BTC on our recommendation, spends it successfully, is generally happy with Bitcoin... but then watches as the BTC price rises... their initial positive impression is probably going to be replaced with a "WTF did I do? If only I'd kept that 1BTC and spent fiat instead
What a rip-off!" (unless they took your advice and replaced the BTC they spent - but that's hardly convenient compared to fiat. I'm still going to use fiat for coffee!)