Honestly - mostly for fun.
I don't consider Steem to be money, but to be a kind of spending token.

I like the community, the spirit of many Steemians, the content I can read here (a bit too much of conspiracies, but that's another topic ;-)) and I like the system that I can reward content producers directly. I haven't seen such a thing in any other place. I like being able to incentivize Steemians to continuously produce content here (though my stake or the price of Steem currently is too small to incentivize people substantially).

I don't like the Whale structure and I think Steemit Inc. has been managed very poorly (possibly Ned doing too much coke). I think the premining of Steems was not the perfect start. But I think Dan, Ned and some Whales did the work in the beginning and they have earned a substantial stake of Steem.

I think and hope that the community (in cooperation with the new management of Steemit Inc.) can take over and - step by step - improve the governance of our network, the reward mechanism and the user experience (e.g. Steempeak).