Thanks for that clarification.
There are different ways that a "gifting" plan can be set up. It appears, however, that in practice, most of these are plans or programs (or some would say "schemes") where people give cash with the hope or expectation of receiving more cash from others in the future. If you Google this phrase ("cash gifting"), you can find articles all over the map on whether this is legal, and whether it is a viable business.
As for the legality of it, it appears to be suspect. First, any act of deception or fraud is illegal. Thus, for example, if someone recruited others into the program with unrealistic statements about the recruit's prospect of making money, that would violate several laws. At a minimum, most states have laws against "unfair" or "deceptive" acts and practices, and of course laws against fraud.
There are at least a few cases addressing these types of programs. For example, in Oregon a person engaged in gifting was charged with a Pyramid scheme. The court wrote, "First, plaintiffs insist that their activities did not violate ORS 646.608(1)(r) because NWFR did not require a $2,000 investment as a condition to the right to solicit or recruit additional participants. In particular, plaintiffs rely on repeated representations by NWFR organizers and participants that anyone could talk about NWFR's activities and anyone could encourage, solicit, or recruit others to participate in NWFR. Said another way, no one had to be a participant in the gifting club or pay for a position on one of NWFR's boards to be able to encourage others to participate in NWFR's investment scheme." The court rejected this argument. This case is: Nielsen v. Myers 193 Or.App. 388, 394, 90 P.3d 628, 631 (Or.App.,2004). I do not know if this is available for free on the internet, but it seems that you can pay for the entire opinion here:
In a case from Texas in 2005, a woman was convicted of engaging in a Pyramid Scheme, even though she contended that she thought "gifting" was legal. King v. State, 174 S.W.3d 796 (Texas 2005).
You would probably need to provide an attorney with more facts and documents about this particular program. Certainly, the mere act of giving a "gift" is not illegal, but these programs (or "schemes") are probably afoul of the law.