Well, its well known that people copy-paste content from sites such as ezinearticles and articlecity etc..Doesn't it affect the article site itself?? plus, people use article submission scripts that submit the same content to many article sites..won't it lead to content duplication among themselves???? wont google slap them for all the above reasons??
rome, if people copy content of any article in ezine or any other article site, it doesn't affect that article site but if you paste that content in any website or blog that is considered duplicate content and suffers problems like spamming or penalties by Search engines....
But how does Google know which one is the original content??? i mean what if the content is copied from a blog and submitted the article site??