Piggman-
I haven't read ALL of the posts so my question may have been asked already, but I'll ask anyway. Are the pictures oriented the same? Example: If you're looking at one side of the item and turn it over on the left / right axis, is the top of other figure "at the top" ? If so, I have another idea for what they may be.
The hex shape of the items may be to keep them oriented in an overall display picture / holder designed to be viewed from both sides. An example would be a display placard made of thin plastic with a large silkscreened sports picture as a main feature, surrounded by a ring of hex-shaped holes filled with these "pigg nuts". The hex shape would act to keep the "nuts" from turning in its position. They would form a "halo" around a central, major display.
Just another guess, but those hex flats must be necessary and used for some reason because making a round die for their manufacture would have been cheaper than making a hex shaped die.