Why do a good many dog owners walk dogs in neighborhoods and allow them to potty on other people's mailboxes, driveways,

[volcs0]

I think it's all gross. I see dogs walk up and down our sidewalk in front of our condo - peeing on the trees, walls, whatever. Most owners pick up the crap, but I still can't help bring disgusted at the thought of my kids traipsing through there when they go out and play. Feh.