electrostatically charged dry sweeping pads

I was looking at dry sweeping pads, as for a Swiffer, and this one says it's electrostatically charged, but none of the others, even more expensive ones, say that:

Does anyone know anything about electrostatically charged pads/rags?

How come these cheap ones claim to be charged but not the others?

Is there any way to charge a rag or paper towel I already own?** A vandegraff generator would do it, but the cheapest one is is $144. (I thought the one they used for a few minutes in high school was a toy, but it must have been too expensive to be a "toy".)