The African Caravan of false ads

I finally had to make an account just to ask about this, because I'm curious. There is a gathering of false ads with black women traveling around the country in the small towns. No verified pictures in any of them. The names and pics change with time. One or two look like they could have real pics, though with the faces covered. It is very clear that they all come from the same source: Usually similar-sounding names, similar style in the pictures and other details.

They are obviously not six to eight girls traveling together. I suppose there may be two. So what is the purpose of this? Why not just have two ads? It must be a lot of work to take care of up to eight phone numbers. Unless there is a way to add several numbers in the same phone. Also, the ads will cost them.

I tried to think of a reason and I came up with this:

-Try to see which pictures work best. (But they should have learned that by now, it's been going on for a long time.)

-Want to make a customer come back to the same girl. (But he would be pretty annoyed if he goes to one girl, then calls another ad and it's the same girl. Plus, if they stay only two weeks, how many customers return within that time?)

-They imagine that customers choose a girl more or less randomly. So that if they have eight ads they are more likely to be picked than the few other ads in a small town.

-Crowd out another black girl who is in the same town. Even if a customer realizes that so many ads will mean that some are fake, he won't know which ad isn't part of the scheme. (But there isn't always another black girl in the same location.)