laces have touch the ground in bathrooms and filthy places, thus mopping up urine and sicko things all over the place. I will tie shoes, etc, but I will immediately go and wash my hands.
Serving a mission in Brazil helped cure a lot of my Germ-a-phobe tendancies, but shoe laces is not one of them...I know it is weird, but I don't care.
Most of my shoes I can slip on (Nike Free Runs, etc) and it doesn't really bother me too tie my own shoes anyway, since I make sure the laces don't touch the ground when I have them tied, but kids....that is another whole ball of wax, usually their laces are long and drag everywhere, I avoid touching them as much as possible.