Plurals

An old classic -- A town had undergone a bitter fight over sex-ed in the schools when a woman's daughter comes home from first grade and announces proudly, "In school today, we learned how to make babies." The woman had been in favor of teaching reproduction, but to first graders? This seemed absurd. Trying to keep her cool, she wanted to know exactly what her daughter had been taught, so she asks, "How do you make babies, sweetie?" Smiling, the daughter replies, "Easy, Mommy, drop the 'y' and add 'ies'."

But do you always? We happen to have two people named Gary in the department this year (mind if we just call you Bruce?) and I've had cause to refer to them both both in writing an e-mail prompting the question, What is the plural of "Gary"? Is it "Garys" or "Garies"? If it is the latter, why do we treat the linguistic symbols for names differently than other words?