For a lot of people they are unemployed and when joining SFI they can do this business on a shoestring.
For others they could be retired and this gives them something to keep themselves busy instead of being bored.
For a lot of others they already have experience with the internet and, being in business for themselves, so this would be a piece of cake for them.
For others they like a challenge and this would be something of interest should they really want to get involved. There are so many ways to make an income with SFI
Those are just a few reasons that I would think someone would want to take a chance with SFI.