Sliding head first into 1st base.

You see this maneuver many times in a season and yet it seems someone always says "you should never slide head first into 1st base." So, why is it still being done? Why do baseball players still dive into 1st base when the risk of injury is great. Furthermore, why do players dive when you move faster sprinting then diving. Are these players just morons or is there a practical reason to do this?

Well there is a reason but I don't believe it outweighs the risks.

Ostensibly, the dive into the bag is done to avoid the 1B's tag. The 1B moves off the bag to receive the errant throw. When the 1B comes off the bag, he will be looking for a runner to tag. The play is designed to remove that tag opportunity away from the 1B. If you see the 1B come off the bag, dive to avoid him.

But, in order to hold anyone acocuntable for such a play you have to practice this play. Is it really worth having players run full speed down the baseline and dive into the bag while reading the 1B in the process?

Sorry, I don't see it. It's just not worth the risk.