I see what you mean - but that implies getting interested parties to invest in steem power first (so that their "upvotes" can entice people to have a look at their ads).
And that is precisely Steemit.com problem - focusing on the blockchain they were not very successful (to say the least) at bringing investors to the blockchain and making them power up in sufficient proportion as to at least keep the price of steem at a cool 0.35 mBTC for instance (while Steemit.com would power down and sell STEEM to pay salaries)