Why can’t you?

“Sent from my iPhone.”

Any time I see "Sent from my iPhone" I assume the sender is a fool

Are you missing the point that adverts can be inline with normal content and therefore can be included in an API result?

You could, but with EU and other legislations you'd have to make it clear it's an ad, so in API-speak, there'd be a "is_sponsored=true".

That makes it too easy for API consumers to ignore. (Compared to human eyeballs browsing a webpage)

But you could make it part of the ToS: if you're using the API to present posts to users, you MUST show all the posts in the list, including the is_sponsored=true ones.

Even though reddit probably don't tag the ads on their website deliberately, it's still really easy to block them in a browser

Even so, how would you track impressions?

That's a good point, UK Government page on "Guidance: Hidden ads: Being clear with your audience":

https://www.gov.uk/government/publications/social-media-endo...