I used to go door-to-door selling candy bars from school in my immediate neighborhood, but that was in a completely different time when kids could safely do that.
I don't agree with the kids being completely absent from the selling places and process. But I can understand why parents don't want to send their kids out solo to private homes.
My neighbor (two doors away) goes with his kids door to door for safety reasons. Sounds like a good compromise.
I usually do not buy if only the parents are selling. If the kids are there actively getting my attention, I always buy something.