Hi @charismaon,
The issue of self promotion and promotion of Steem is of course a pretty big one which you're right to be concerned about. Steem is a Decentralized Autonomous Company (DAC or DAO). Like any company, it has development, marketing, content creation, business intelligence and many other 'departments', only those departments are themselves decentralized and autonomous. It is of course in the interest of Steem to market itself, get the word out, just like any company with their product. It's important also to improve the product itself via development and to ensure its long term viability, and to create content which keeps users engaged.
Those aren't always connected. Sometimes the marketing is going overboard while development is stagnant. Sometimes marketing is ineffective while development behind the scenes is making great strides. In the short run, people will pursue marketing for its own sake (and there will be pump and dumps), in the long run the product has to be worthwhile for Steem to remain relevant in the marketplace.
If you believe that there needs to be less focus on marketing and more on development (or some other area), then one of the great things about Steem is that if you have the Steem Power, you can direct funds towards that goal yourself, without spending your own money. You get to be part of that executive process.
The topic of 'where the money/value comes from' is a pretty big one which I won't address in this comment, but it is pretty important to get your head around and decide for yourself whether you believe it's sustainable or not.