it's understandable that the questioner would be concerned about a currency who's value changes radically at times, but when you look at the long term charts, it would seem that more and more businesses would gladly accept them once they understand the risk/return.
Imagine selling one computer to someone for 20 BTC (when bitcoin was $65 = $1300) earlier this year, and keeping them safe in a cold wallet. Meanwhile all the others you sold with USD. That one computer sale would now net you close to $8000 so far. That's not a bad profit from simply having a "buy with bitcoin!" button next to your product.
And remember, as more and more people accept and use it, it will be more like using a dollar, where things will be priced in such a manner that it won't matter the value of a dollar, it will be, "How much is it worth in bitcoin". The hardest part about this whole thing is that it's going from the bottom up. We, as consumers are trying to get merchants to accept it, and the merchants either need to convert, or get their vendors to accept it, and so forth. If we could get a very large vendor to accept it as payment for something that many people purchase and resell, then we'd really have a decent grasp on the economy...
Patience my friend... all in the right order