You’re just rephrasing the original question. Ok so why would someone design a tool that takes screenshots if tiny blurbs of text? It truly boggles the mind.
Okay, maybe a bit of CSS could do the same. But this requires someone to change the CSS. Adding an image can be done by any journalist and is mostly risk-free. You cannot break the looks of other articles this way.
This, of course, is only to argue why such a tool exists.
For any other medium an article can just quote the content.