I was told to put Kitty Litter in my new speaker stands. Was he joking?

I guess i realize he was NOT joking, but it seems strange. I've always heard sand was best. He told me to get unscented kitty litter and fill em all the way up. The stands are 29 inches with 4 columns (2x2). Monitors are 23 pounds each.

Anyone done this with a positive result?