Yeah, what Ed said.....if you use earbud phones you won't be able to drown out much of anything....because that's the way they were designed. So you could hear a car coming at you down the road when you're lost in your own little musical world.
Just for the record, I believe that all personal music devices are set to a level that won't cause permanant hearing damage. That's why it doesn't go that loud.....
And yet another thing, if you don't like the volume setting, and you purchased your player through a repurtable retailer, you could just return it if you're not satisfied.
Another thing you could try is the eq settings. Us guys hear more bass than women do so you could check which eq setting will give you louder bass frequencies. I'm not sure if ipods allow you to set your own or if they only have presets. Either way you should be able to adjust the sound to your liking. Come to think of it, you might even be able to modify the upper limit of the volume control. If you want to be proactive you could always go to the various manufacturer sites and read the manual before purchasing a unit.....