they knock on residential doors too, they pester inboxes. Most all of it junk we don't need. It's not just MLM's. I hate MLM's too...even though I have used a few MLM products over the years that's weren't bad. But I think it's a bit of a tantrum by the OP to single out some low income households that are pushing some products to pay the mortgage. Just say no. If they keep pestering you, don't be their friend, get off facebook, etc.
But I've had more sales people come into my office trying to push "Mailers" "Crappy thousand dollar vacuums" "Overpriced copiers" "stinky overpriced cleaning products" then I've been pushed to get into an MLM. Capitalism never stops. It's part of life.