They're created by someone and written in their native language, which in turn attracts a community that can communicate in that language.

why are most English websites English only? They are all created by the Brit?

Because most of the native English speakers are monolingual.

what point are you tring to make? Because mine is that it has nothing to do with "native". There are more English speakers, native and non-native, who are multilingual than speakers of any other language, yet they chose to make content in English, instead of multilingual to reach a wider audience.