Because of the nature of recruitment and the dream of living the life of riches, it is no stretch to the imagination that sometimes, the real picture gets blurred between the lines. Also, MLM is notoriously known for getting you on the bad books of friends and family. This is of course a general stereotype against the industry and not a concrete consequence.
The legal distinction between MLMs and traditional pyramid schemes has been characterized by many authorities as a legal fiction. Jurisdictions that retain a legal distinction between MLM pyramid businesses versus illegal pyramid schemes retain said distinction on two key distinguishing features: 1) that MLMs always encompass the sale of actual products/services, while traditional illegal pyramid schemes ordinarily do not (though sometimes they do), and 2) that climbing an MLM pyramid is overwhelmingly statistically improbable (especially to its highest participant levels) but not theoretically impossible, whereas climbing a traditional illegal pyramid scheme is both statistically and theoretically impossible.