Believe it or not, we're still in the early stage of bitcoin, it's not widely known around the globe as of yet, but once it becomes mainstream, we might see the price becomes stable as more people beging to use btc. But I think it would take decades before a cryptocurrency can be adopted as a currency for daily purchases, some stores in europe and asia already implemented the use of btc, but we're still far away from what bitcoin can actually be as a currency to society.
Also, you are comparing btc with fiat currency so your example doesn't make sense. If a pizza costs you .002 today, after a big surge in the btc price, it will cost you the same .002 btc.
I wouldn't say this is true about the early stage of bitcoin, as we've pas through the early stage by a long shot now. As the early stage would be the first time it was invented and used, by Satoshi himself.
Moving onto the thread, I feel that these days Bitcoin (like most other altcoins) are trading coins and not really currencies that are used to do as they were made for. While Bitcoin is used more then most altcoins, I feel that it's still more of an investment then a currency.