I've seen posts on here that weren't very well written, and made little sense. I just thought those were written by non-native English speakers. I've also seen the really general ones that could be about anything if you just change out a few words for new words, and assumed the person was just trying to write in a topic they knew little about, hoping to get upvotes.
It never really occurred to me that plagiarism might be going on here, because it's so much fun to write original content on topics that actually interest you (something I rarely get to do as a business writer....my writing is original, but it's for clients, and it certainly doesn't interest me). Why plagiarize when you can write something cool on your own?
But, I guess there are people who are looking for a "formula" for making money here, and using spun content to do it. I know all about those spinners. I've seen other freelance writers who cater to the internet marketing community offering to sell an original article that they will then spin into three or more different versions, so their clients don't get dinged by Google for duplicate content on their websites. It amazes me people still use spinners, but apparently they do.
What people don't realize is that the best formula for making money here is to write original content that interests you, on topics you're passionate about. That passion will come through in your writing, and your audience (and maybe a few whales) will find you, and upvote you.