I think the native speakers tend to make many more complex sentences than non-natives. We embed, we omit, we sometimes try to join many thoughts into one sentence. So it's not correct or incorrect use, but how complicated are sentences are, I think.
And Wombat, as I was reading your post, I thought "Is this guy really not a native speaker?"
We make SO many mistakes, and that's why I chose my name here - among native speakers, people do call me a grammar geek, because I'm the one who is more likely to know "the rules," but after coming here I realize how poor my knowledge is. People who are learning using a grammar book have names for parts of speech I've never heard of! To think I'd lived 39 years before ever hearing the word "ergative"!