It's exactly as easy to decrease VLC's audio level back to normal as it is to increase it.
Anyway if you don't like it remembering the last audio level, go to Tools > Preferences > Audio, check the "Always reset audio start level to" box, and set it to 100%. Voila!
No, VLC should remember the last audio level, just not when it's over 100%. If I leave it at 50%. On next restart it should be 50%. If I'm watching a movie and finish on 200%, on next restart it should be 100%.
Clipping sucks. VLC shouldn't remember these options unless the user changes an optional setting.
I have to be honest, setting "do not remember audio" sounds like a decent compromise between not getting anything that you want and getting exactly what you want. It is especially appealing since you get VLC and this compromise solution for free. However if you are still not satisfied:
Anyway if you don't like it remembering the last audio level, go to Tools > Preferences > Audio, check the "Always reset audio start level to" box, and set it to 100%. Voila!