From what I understand, if you get emails without you subscribe them. It's probably a scam and at the same time a spam. Usually, when you click the link, you will be directed to a website, with lots of (sometimes a little) of ads, pictures of users taken from google image with fake reviews and a guy (paid actor) talking in a video which spans from 15mins to 1 hour.
I would say, all of it are scams if the offer is too good to be true. From email processing to 'investment', because that's what they do. Scam people with unbelievable offers such as mak $500 per day or something like that.
If you observe in those websites, usually they have the same pattern and a quick Google on those websites will usually bring scam reviews about them. No one I think have succeeded in actually making real money from them. Even by clicking their ads, you've already generate them money from the ads they put.
Be careful out there.
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