There is a lot of social pressure to conform, sometimes too much. People fear what they don't understand, and often ostracize people who are "different". There are so many different personalities and people are unique, so why not let people be who they are? It's not fair to hurt people we see as different.
No, it is horrible to stigmatize or bully people because they are different. We should be cultivating behavior in people and children to be themselves, because we need a wide array of people on this planet to keep things interesting and awesome. It's mean and closed minded to consider someone who is different to be fodder for bullies.
I was rasied to be one of those people who never judge a book by its cover and treat people who may be different or slightly "less fortunate" more negatively then anyone else. I try to treat other people with respect, and treat them the exact same why I would like to be treated.
Society should not stigmatize people for simply being different than other people, that is a bad way of doing things and does not establish a good standard of living for anyone. People should be allowed to dress and act however they choose and highlight their differences rather than be afraid of them.
I think one of the worst traits America has problems with is that we are extremely intolerant. We try to project one ideal of equality and fairness, but at the same time that's not at all how society operates. We should have learned by now that stigmatizing people because they are different, is wrong.