Is using proper titles in social situations pretentious?

[Clodfobble]

“A physician is always addressed as Dr. so-and-so,” wrote Margaret S. Choa, MD. “It’s the proper title. Always. In any situation: business or social situations.”

I suspect that her idea of a "social situation" is a formal cocktail party thrown by some rich dude who barely knows half his guests. If she makes the other moms at the soccer game call her "Dr. Choa"... well then I'd imagine it's not an issue, since they won't actually talk to her.