Look at the shoes below the child. Just like a hankercheif below a rape, the shoes act as a symbol of the act of spilling blood of a child. It's caught in/on and stains the leather shoes and act as a momento.
The shoes we see worn in public (podesta with the group of young men, pope, Bill Maher) may not be these exact precious (to them) momentos. They may be otherwise dyed shoes that are a symbol that reminds them of their real blood soaked shoes that they placed under their kill to remember, yet can't wear in public.