This is it. I’ve worked on plenty of projects that have web/iOS/Android, and the reason for offering native apps has always been user demand. All of this “spy on the user” crap literally never even comes up in conversation. We don’t care at all. We care about native apps because users care about native apps.
I think this is probably more true than not in terms of proportion of apps that offer a native client interface to an existing web service, but I don't think it's true for Reddit or other large companies who's primary business is selling advertising and data.
> why do so many websites try to push you into using the app
It you’re talking about the intrusive stuff that gets in the way of you using the website, then the answer to this is pretty simple: they don’t. The sites that do that are comparatively rare. They just appear more numerous than they really are because it’s the really big sites like Reddit that do it. The norm is either a page on the site that tells you about the app, or the banner that appears at the top of a page.
This is it. I’ve worked on plenty of projects that have web/iOS/Android, and the reason for offering native apps has always been user demand. All of this “spy on the user” crap literally never even comes up in conversation. We don’t care at all. We care about native apps because users care about native apps.