The mindset that YOUR culture is better than all those other cultures out there. The way your ethnic group does something is quite simply the only way to do a certain thing, and no other way has occured to you. Can be a function of ignorance as well as arrogance.
The shock when residents of middle eastern countries see American women that are in public unveiled. How can those ruffians allow their women to be seen that way? Also the shock when Americans see that middle eastern women aren't allowed to be out unveiled or to even have jobs.
A more notable one perhaps, and one that I take personal issue with, is male circumcision. It is standard in US hospitals to circumcise male infants. Yet female circumcision is considered horrendous by western culture. Yet in many states in Africa it is considered quite normal. Ethnocentrism at it's best, if you ask me... I want my foreskin back