Cant I ask that about pretty much any Crypto?
What is my incentive to hold large amounts of ETH despite speculation (after the switch to pos it is a different story)
Why hold Tezos if not for staking and speculation?
Steem is solving issues not many people have at the moment and I think there are so many misinformation out about it which is a problem as well.
Creating an environment that promotes the usage is kind of a backdoor way to making steem relevant. @Exyle has the point when it comes to why we will one day need to own and hold steem. Whoever holds steem today, may as well be a bank in the future.
One could even say that this is the internet of tomorrow since we're all sort of building this protocol that may well be the next generation protocol of how people transact and interact on the web. Steem can be easily replicated once its done, but first movers advantage is a massive advantage (ie solving problems before they are problems).