I can't say a lot J. Rios, italki is heaven comparing to other sites. It happened with me once that someone called me names in a private messages, but I blocked him and I never responded because he don't deserve even a second to think about him:)
So I guess there are some cases but I can't so a lot. Mostly there are cultural differences, but you would be amazed from the similarities you discover between members from different parts of the world as well (,")
I don't know that I would use such strong words to describe what I feel is more of a culture shock. Many times people who have no experience with another culture may come across as stand-offish or rude in the ways in which they deal with their lack of knowledge. After all, "if my country/culture does or says a certain thing, isn't that the way all countries/cultures should do it? And if they don't do it my way, isn't it my job to teach them 'what is correct'?" :)
I think that the more a person knows, the more open they are. Humans are naturally wary of the unknown, and there will always be people who are more or less friendly than others. I think as a whole, however, italki is a friendly place to learn about other cultures and customs. There will always be bad, just as there will always be good. It is our job to seek the good.
Sometimes yes but most of people here are nice.
I didn't noticed any racism here.
The closest I've come to that was a guy who said that he didn't want to talk with me because I'm American. He said that he added lots of rude Americans on this site and that they made many racist comments. Pot meet kettle.