Key Chain Blues

Every day I see the people of my neighborhood drive up to the mail box stand, then turn off their car so that they can get their keys out of the ignition. Then they open their mailbox with the mailbox key which is part of their overall key chain, close their mailbox door, insert the car
ignition key, and drive on.

After hundreds and hundreds of times of doing this, you would think that one of them might stumble upon the notion that since they always get the mail when they're in their car, there's no reason to have the mail key as part of the same key chain that holds the car key. Their mail key could be housed independently someplace in the car. where no one else would know what it is. and be used at the appropriate moment to open the box, while keeping the car on, and then driving off.

You wonder, if they can't figure out this component of getting things done, what else can they
not figure out?