First thing to understand is that Steemit is NOT paying its users, Steem blockchain is. Stemit is just a web frontend to the Steem blockchain.and there are several of them. So even if Steemit inserts advertisements and earns from it, its users won't get any share in it.
Secondly, if you think advertisement could help fund user rewards then why do ad revenue should go to any mediator and then redistributed? The money can directly be paid to bloggers depending on the number of views / clicks their blog posts got for those ads.
For people like you who don't love advertisements, bloggers can be given the option for whether or not to insert advertisement in their blogs. So those who don't insert advertisements won't earn any advt revenue.
Finally, insertion of advertisement is a done thing and going to happen soon. You can't stop it. Keep an eye on projects like @steemads & SMTs.
Users will always find a way to earn additional revenue. Why should my blog post earn only within first week through upvotes when it continues to receive views in future too. And why should my blog post be rewarded only from the upvotes from Steem users when I share my posts on several social media and also get non-steem users to my post from search engine results. I know not everyone can join and become active on Steem. Steem isn't meant for everyone of them out there. But my blog post can definitely reach beyond Steem users too and that is what always intended by any author. So shouldn't I earn some revenue from those views?
Congratulations! Your submission earned you 0.011 STEEM from this bounty. You have received 0.011 STEEM from the creator of the bounty and 0.000 STEEM from the community!