Yes, but we already have Bitcoins so why would we want another crypto-currency for trading goods. No one uses altcoins to buy goods and services ... and if no one had started doing it with bitcoin it's value would be zero by now. The speculation can last for a long while but in the end it needs to pay out with a real use for it. Some crypto-currencies have better anonymity or better integrated features for crowd-funding and so forth and can last this way by adding to the financial functionality of Bitcoin.

The only way to use the Steem Dollars I can see now is to buy influence or to promote posts. Are the tokens destroyed when promoting posts? If the inflation also redistributes the Steem and Steem Power ownership ratio toward the most active users maybe it could work. Still I think there needs to be more on site ways of using the tokens really....