Do you know in the outside world that if you say you are an Indian, a lot of people will simply assume that you are a Muslim. After all India does have the 2nd largest Muslim population in the world.
Similar to how if someone sees a Korean they are likely to simply assume that they are Chinese or Japanese. Or vice versa. The human mind is prone to stereotyping due to compartmentalization of information, it's just easier.
I often have to correct a lot of people by telling them that India is in fact majority Hindu. And that Hindus avoid eating beef while Muslims+Jews avoid eating pork.