I'm using it in my games (as shown above) so yes it's useful, at least for me <img src="smileys/smiley1.gif" border="0" align="middle" />.
For example if you have a vertical shooter where your ship goes up and the scenery and enemies etc go down. There's a "tall" layout, and the player fires some bullets up. Those bullets can potentially go all the way up and kill the boss which is like 5 screens up and the player has not reached him yet. I would like the bullets to be destroyed outside screen (and I destroy them as shown above).
I know what the "Destroy outside layout" was designed for and I agree it is useful in many circumstances.