Get used to it, Marcio. Glad that you are a perceptive guy. As for English natives, many of them learn grammar then "unlearn it" and relearn at their will. In fact, many will focus on the sound rather than grammar (the written form). A writer of an EFL book did a research and some participants commented that good English (being correct pronunciation) is a matter of education, and not of being a native speaker.
I think same goes to writing more so with media, that sometimes has demanding schedules, lots of news, change of hightlights, and so on.