I see there as being essentially two major categories of people who call themselves Christians. There are people who are just trying to love their neighbors as themselves, do to others as they'd have others do to them, not judging, etc who pretty much leave other people alone. They believe in democracy, the U.S. Constitution, freedom of religion, secular government, a separation of church and state and basically see religion as something personal rather than something that should be legislated. Based on conversations I had with a bishop, I'm just going to refer to these people as Good Christians.
Then there are the Fundamentalists who go around telling other people that they're going to be tortured forever if they don't believe in their book, legislating their religious beliefs, working for hierocracy (rule by religion) as opposed to democracy, opposing the First Amendment and our national values of freedom of religion, separation of church and state and secularism. They persecute other religions and various groups of people, including gays, Lesbians and women, who are just minding their own business, obeying our laws and living peaceably. In extreme cases, Fundamentalists even commit hate crimes and other extreme acts of hatred. Recently, groups of them have gone to other people's funerals to "protest" the funerals. Over the past few decades, extreme Fundamentalists have even murdered people. Having Fundamentalists physically assault someone or damage someone's property just because that person has a different religion or is one of the groups that they hate is relatively common.
I don't know which group you're in. If you're a Good Christian, I'm sorry that people are attacking Christians in general. I think they should try to make the distinction that I made above. I do think, however, that much of the attacks and insults aimed at all Christians come from people who are angry about the Fundamentalists. So, if you're in the Good Christian category, turn the other cheek and realize that a lot of this stuff may not really be aimed at you.
If you're a Fundamentalist, however, "how can you see the mote in your brother's eye when you cannot see the log in your own?"[1] Fundamentalists persecute others. Fundamentalists do to everyone who's not one of them all of and more than what you're complaining about in this question. If you want people to respect your religion, you need to respect theirs. You ask if people make fun of others because it makes them feel good to upset people. Personally, the only theory that explains to me why Fundamentalists persecute others is that it makes THEM feel good to upset people.