Every time I search on my wife's iPhone for some specific application in the App Store the first result is an add for a competitor's app. How is that 'expected'?
I search for apps in the App Store once every few months. Perhaps others do it once or twice a week if they like exploring and trying new apps.
Does that not seem qualitatively different to you? Even if Apple makes some revenue as a result of advertising inside their fully segregated marketplaces, it's hard to think that those ads are a big part of one's experience with Apple.
I don’t like ads in general, but “you searched for a competing product, please consider mine” is so old school and understandable.