It's main purpose is to keep the grift going; guaranteed that Trump\family is getting a certain percentage of all mailings that have RNC\associated Committee links plus a certain percentage off of all WinRed fees as well as all contributions to RNC various campaign committees
Direct mail is by far the lowest return on investment for campaigns. Any difference made is very negligible.
It's main purpose is to keep the grift going; guaranteed that Trump\family is getting a certain percentage of all mailings that have RNC\associated Committee links plus a certain percentage off of all WinRed fees as well as all contributions to RNC various campaign committees