I think it might be a filtering thing, like Nigerian scammers including things that make them look dodgy to make sure they've got someone particularly gullible

I think it might be a filtering thing, like Nigerian scammers including things that make them look dodgy to make sure they've got someone particularly gullible on the hook. The people who end up subscribed to the newsletter are the easiest to get money from, sell junk to, con into buying cryptocurrency, scam, whatever.