This is complex question and it depends on where you are located.
Some countries have banned it, others have warned against it and even in countries like the US where it is legal, they've been demonstrated behaviour that at least makes it undesirable to be a part of.
The simple conclusion is, WorldVentures or DreamTrips both is and isn’t an illegal pyramid scheme, depending on what country you’re talking about. But no matter where it operates, legal or not, you should be very suspect, if not simply avoid it entirely.
There are both better ways to travel and better ways to make money – focus on those.
