I've seen what some of them do, and it's not as impressive as you'd think. Most of it breaks and stops working inside of 24 months. Then it's on to the next scam. Not a lot different from fly-by-night snake oil salesmen.
Just the existence of spam doesnt prove it's a big oppotunity, just that it's better for some people than their opportunity cost.
Just the existence of spam doesnt prove it's a big oppotunity, just that it's better for some people than their opportunity cost.