The message will pop up immediately when posters click on Post button, so if they try clicking on Post button the second time to publish their posts, it means they don't care about the topic, instead what they care about are their postcount, post quota.
In addition, as you said, it is definitely the common behaviour of account farmers. They usually don't care about topic's contents, flow of ideas and discussions. They tend to jump directly to the last post, and reply to only the last post.
Real users will behave very different:
- They read at least the OP, and the last posts (not the last).
- They have to scan pages (if new topic, scan all pages; if old topics, scan a few last pages)
- Then, they organize what have been solved, what have not been solved before composing their own posts to discuss.
- Sometimes, they edit their posts to improve their contributions and better express or clarify their ideas.
It means real users spend long period of time to read, before they start composing their posts, and they might give up their posts if eventually they feel like their posts are un-constructive, off-topics, or questions already answered with previous replies.