[geoffmunn]

I am 100% convinced that the baby weight thing is because grandparents love to compare newborns with their own experiences, and they were on the cusp of the metric conversion in the 60s. In a decade or two, this will vanish.

Imperial height is because 6 feet is the generic height of a "tall person" - we get so much of our sporting news from overseas and no one bothers to convert it.