So some of these servers that were wise have only paid everything (servers, wages, etc.) using the real currency that comes in via credit cards and paypal and have just held onto the btc .. which makes it extremely valuable.
But people don't set prices in btc. The prices are set in fiat currency and are paid for based on the price of btc that day .. meaning you could have spent 10euro for a service last year in btc that would have been worth 100euro .. or that could be worth 0.01 euro depending on where the market goes.
But yes you're right, unless services start pricing actual service in btc, it's not really fungible for goods. It's always going through that translation layer. If anything, if McDonalds started taking mBTC and charged x mBTC for a burger and didn't change that value with the market, you'd start to see bitcoin stabilize (although you might be paying $100 for a burger some days .. if you go by what the exchanges claim the value is).