Putting minimal, non-obtrusive advertising on posts that have already paid out makes so much sense. It will make the value of steem come to a boil. The house takes a cut, the author takes a cut and the community gets a small nugget.
I truly despise websites that have become too clunky to use, due to pop up advertising. It can be done in such a way that everyone profits.
You raise a point that I completely overlooked. The value of STEEM could explode if some clever "official" advertising mechanism was introduced to Steemit.
Right, an actual revenue streem into steem versus investment and inflation. Could work nicely.