Despite the fact that the holy scriptures of various religions e.g. the Holy Quran as per the following verses state that we should not scoff at others and that God has created all men from a male and a female and divided them into various nations and tribes so that they may know each other better, we mock at those who are different from us:
49.11. O you who believe! Let not a group scoff at another group, it may be that the latter are better than the former; nor let (some) women scoff at other women, it may be that the latter are better than the former, nor defame one another, nor insult one another by nicknames. How bad is it, to insult one's brother after having Faith [i.e. to call your Muslim brother (a faithful believer) as: "O sinner", or "O wicked", etc.]. And whosoever does not repent, then such are indeed Zalimun (wrong-doers, etc.).
49.12. O you who believe! Avoid much suspicions, indeed some suspicions are sins. And spy not, neither backbite one another. Would one of you like to eat the flesh of his dead brother? You would hate it (so hate backbiting) . And fear Allah. Verily, Allah is the One Who accepts repentance, Most Merciful.
49.13. O mankind! We have created you from a male and a female, and made you into nations and tribes, that you may know one another. Verily, the most honourable of you with Allah is that (believer) who has At-Taqwa [i.e. one of the Muttaqun (pious - see V.2:2)]. Verily, Allah is All-Knowing, All-Aware.
In fact, a North Eastern young man was mocked at in Delhi by North Indians and when he objected, he was beaten to death. This is really horrible. I have seen people similarly mistreating Africans in Delhi and calling them blacks. This is not desirable. Similarly, when I was in Punjab, I was called names because I was not a Jat and was not considered a Sikh by Jats as they wrongly felt that only Jats are Sikhs. This is a casteist approach and needs to be avoided. Similarly, on the basis of religion, we scoff at each other. We also mock sometimes on those who do not speak our language and this often results in serious repercussions. This not only happens in Delhi, it happens all over the world. The white people often deride brown and black people and so on. Many times, we mock at those who do not belong to our gender or who have a different sexual orientation than us e.g. Lesbian, Gay, Bisexual and Transgender people. We should respect each other and live with each other peacefully as this whole earth belongs to all of us.