You need to set notifications in settings, We do not allow posts from steemit to show up not changing.
Ad's might suck but they keep the lighst on, we allow image hosting, video hosting and more. The current amount of users posting isn't enough reward and running an application plus a business requires some input of income and not just output. Also the ad placement is only in one place and not all over the site like a spam. So it is targeted ad placement.
Also you can find replies to your post on your profile.