I think greed and laziness is saving them from themselves. Take note, because greed and laziness make the marble spin.
Most people making bank here don't really understand STEEM/SP/SBD. But they understand that every time they log in the SP balance is a little bigger. That is good. In order to make good into more good, 98% of do-gooders are converting earned STEEM into SP. That's probably going to end up being the smartest financial decision of their lives. So greed is good.
To dump STEEM they have to create an account at an exchange, which invariably will have an unintelligible and vaguely shady sounding name, transfer the STEEM using addresses and memos and other strange things that make no sense, place a market order with a stop limit and sell it for BTC. Then they have to sell BTC for USD in a different market. Then they have to do some KYC/AML bullshit to get their money sent to them somehow. And they have to do all of this without screwing up or they loose their money.
Now, how many of your average Steemers are going to take the time and effort to learn how to do all that? Fewer than most of them, I think. So the bulk of the value stays in the Steemit economy. Hell, I've been doing that crap for years and it doesn't phase me one bit. I already have accounts and highroller withdrawal limits. You know what I'm doing? Powering up. Why? Cause it's so damn easy and I'm kind of lazy. Except with comments, apparently not so lazy with the comments.