Well I double-checked my profile settings and I'm definitely not in stealth mode, but my screen name is in italic mode. That's okay. I'm half-Italian and have always had a slanted perspective.
But... http://fhq.forumer.com/phpbb2-general-questions/74764-resolved-what-does-italic-username-mean.html
No need at all, but some Orwellian instinct of self-preservation does lead me, when presented with any choice of 'volunteer info' or 'keep private,' to generally default to privacy absent an actual reason to reveal. I think of it less as a matter of 'why hide' than 'why disclose.'