Do phony people annoy you?

One thing i cant stand is people that are fake, for instance every time i go to the dentist theres this asian lady that works that who tries to act white instead of just being proud of her own heritage, and everything i say she just giggles at and shes like ohhh nice to see you :D and then laughs like an idiot, but you can tell she doesnt care about what im saying... Why do people act like this?