She used an alias that would be recognizable to her classmates -- but, like you, she didn't want her legal name to be easily searchable by prospective employers, health-insurance companies, estranged family members, bad-breakup exes, etc.
But, yes -- having a unique name makes anonymity and privacy more complex. And it shouldn't -- it penalizes people for the name they were BORN with, just because they can't blend into a sea of Bob/Joe/Sue/Tran/Wei names, which are more common.
The ability to create a persistent pseudonym and to use it for unmuzzled online discourse is especially vital for people who would be all-too-easy to track down otherwise . . . but I think that it's still essential in terms of free-speech and privacy concerns for everyone.
http://www.nytimes.com/2012/08/30/fashion/nantucket-benefits-from-a-google-long-distance-marriage.html?pagewanted=all
Probably because of that, I've always been fairly paranoid about using my actual name on most things online, but graduating from a college, participating in research, and having a facebook account pretty much made it impossible to ever be truly anonymous.