People who walk slowly in from of me

Why do so many people walk like they aren't going anywhere? do they leave 3 hours before they go anywhere just so they can mosey on down the sidewalk.
when walking in a crowd, I often have fantasies where i'm in a jungle with a machete, chopping vines and branches out of my way. Only the vines are people and the machete is real. A friend of mine just imagines herself punching people in the back of the head. I wholeheartedly approve
Unless you are old or a child or on crutches, please, get a move on.