The Usenet Oracle has pondered your question deeply.
Your question was:

> O great and sanctimonious Oracle, whose infinte wisdom
> is....well...infinite, whose knowledge transcends time and space,
> whose......aw, enough of this crap!
>
> Why is it that the only time you REALLY need to get somewhere in a
> hurry, some old grandma or grandpa has decided to take a Sunday drive
> at 10 miles per hour and you can't get around them?

And in response, thus spake the Oracle:

} CRAP!? <lightening bolts whizz around you and you fear for your life>
}
} Groveling will get you everywhere.
}
} Your problem is universal.  Let's explore a proven remedy.
} <you are transported from your terminal on to the starship enterprise>
}
} KIRK:"Mr. Sulu what is the hold up?"
} SULU:"Sir, there is a Jupiter IV Senior Citizen shuttle ahead."
} KIRK:"How fast are they going?"
} SULU:"Warp factor 0.00345, sir."
} KIRK:"Chekov, flash the Headlights and go around them."
} CHEKOV:"I've flashed the lights and they won't budge."
} KIRK:"Spock, what do you make of them?"
} SPOCK:"Captain, the shuttle is being driven by a 75 year old human."
} KIRK (muttering):"This always happens.  A planet is being destroyed and
}                    were being held up by the cane and walker corp."
} KIRK (aloud):"Uhura, hail them"
} SHUTTLE:"I am Charlie of Jupiter IV SENCIT.  State you're business."
} KIRK:"There is an emergency across the galaxy and you're in our way."
} SHUTTLE:"We are going the speed limit, sir."
} KIRK:"MOVE THAT PIECE OF CRAP BEFORE I BLOW YOUR ..."
} SPOCK:"Captain, please"
} KIRK:"Move or be destroyed. Chekov ready phasers and photon torpedoes"
} SPOCK:"We have a lock on target."
} KIRK:"Kiss your kiester goodbye. Chekov, fire when ready."
} The enterprise fires and the shuttle is destroyed in a brilliant flash.
} KIRK:"Sulu, warp factor 9.  Scotty?"
} SCOTTY:"Aye captain?"
} KIRK:"I need 110% on the warp engines."
} SCOTTY:"She's got all she can take but I'll try."
}
} The enterprise rides off to save the colony and a valuable lesson is
} learned.
}
} <You are transported down to your terminal and wonder if it was all a
} dream>
}
} Next time pupil, just blast them away with your photon torpedos.
} Warp speed ahead!!!!