The issue here though is the marketing and the promises of wealth/happiness/the ability to work in your own time etc etc. And some of the products are most definitely dodgy and shouldn’t be legal, but IMO most programmes which promote e.g. weight loss are dubious at best,even the more mainstream ones such as lighter life and so on.
But in reality there are some people who will make money doing it. And even if that is minimal compared to those who don’t,the fact that some do is what pulls people in in the first place.
The over marketing of what you’re selling is no different to someone who finds religion or meditation or has some kind of spiritual epiphany. They do it because they’re feeling so enthusiastic about it that they feel that everyone else should want to do the same.
I do think that most mlm’s are most definitely dubious, and I think that most people who are that pushy need to be avoided, regardless of what it is they’re pedalling.
But if someone goes into this line of selling in good faith, doesn’t over promote to their friends and family and just gets on with their life is there really any need to insult them personally?
I have a friend who did pampered chef for around seven years. She absolutely never made a fortune doing it, but she did make enough that she could afford to stay at home while her kids were little. But she never pushed the hard sell, never flooded her timeline with advertising drivel, and actually, wile expensive, some of the PC products were ok, and I have some of mine years on still. PC have ceased trading in the UK now and when they did she had multiple approaches from herbal life/foreverliving and so on, but she was no longer interested as that part of her life had ended and the kids were old enough that she was able to go back to full-time work.
But while she absolutely doesn’t want to be drawn into any kind of selling, she speaks fondly of her days as a PC consultant. It’s fair enough, she did what she did, she never boasted about it, never tried to make claims which weren’t true, so I don’t see the harm really.
Conversely however another acquaintance lurches from MLM to MLM, she’s done foreverliving and then juice plus and then something else, but she’s a highly strung individual who is easily influenced. And her timeline is absolutely flooded with this stuff, and she is not actually open to conversation about it, if she doesn’t like the questions being asked she gets highly defensive. And I managed to get myself blocked by her which I reckon is a bit of an achievement. 
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