Ever seen Jurassic Park? "Life will find a way..." Well, so will human communication. Internet communication has always been more like spoken conversation than written. Written communication is more asyncronous (think: I write a letter and mail it, you write a response and mail it, etc.), or entirely one-sided (newspaper article). That, coupled with the less formal style among the net's users in general, and you get "written speech". It's the same reason we have emoticons. Love them or hate them, they evolved out of a need for non-verbal communication in a textual environment.
You kind of went a little erratic on the "ethnocentrism" point, but I'll indulge you a bit. What you call "ethnocentrism" on the Internet may simply be people using their own language. While you may be the most culturally superior Internet user, not everyone is so blessed.
How it was explained to me was that "err" is the British equivalent of "um". Just replace it (or ignore it) in your head, and carry on. And find bigger things to worry about. This is a non-issue. Relax, it's Friday.