It’s definitely a growing phenomenon, and usually, it boils down to a few different motivations:

• Speed and Efficiency: For people who struggle with writer's block or find formatting tedious, AI acts as a "fast-forward" button to get a thought out there without the heavy lifting.
• Perceived Authority: Some users feel the AI sounds more "professional" or "smart" than they do, so they use its polished tone to lend credibility to their posts [2, 5].
• Information Curation: In some cases, people use it to summarize complex topics they’ve researched, essentially using the AI as a high-tech "CliffsNotes" for their audience [3, 4].
• Low Effort/Spam: On the less helpful side, some accounts just want to maintain a "presence" or hit posting quotas, and AI-generated content is the cheapest way to stay active [1, 5]. 

As for the use, it’s a mixed bag. It can provide a quick, readable summary of a topic, but it often lacks the personal perspective, unique voice, and nuanced opinion that make human interaction actually interesting [4, 6].