Bitcoin is much less volatile than every other altcoin (except for stable coins).  Just because Bitcoin goes up and down by hundreds of dollars makes no difference.  It's all about percentage.  Steem going up by 10 cents is the same as Bitcoin going up by $500. 

Stable is relative, and I would argue that USD isn't stable because it's value goes down every year because the Federal Reserve gets to control all the inflation.  However, businesses are willing to accept USDs "volatility" because they aren't going to go bankrupt from it.  

On the other hand if Steem gets pumped to $10 and a vendor accepts it they are going to go out of business because the price will fall back down and they won't have the money to pay for monthly expenses.  Most companies operate off of razor thin profit margins.  Stable coins pegged to the dollar are absolutely required in these early stages of crypto.  

I'm very much hoping that SMTs will be powerful enough to create a coin like Maker.  The MakerDAO has a platform that let's you lock up Ethereum and pull a stable coin Dai out of the collateralized debt position.  Not only can you use it to take out a loan you can also use it for its stable coin.  It's pretty amazing.