I know I am going to annoy SFB with that but hey I don’t really care.
As foreigner I have bee in situations where my poor english and very bad knowledge of the grammar have made me look daft, or even worth, made me buy stuff I didn’t really wanted or get a service I wasn’t looking for.
I am most annoyed by people (french or english lets face it) that butcher the language under the so wrong excuse to sound cool, or to be an anarchist (a bit like you SFB). Grammar and other language rules exists for a purpose, make the communication between being easier. The same way traffic rules exist to make the journey easier.
You all could ask people who have meet me, and I am sure they all would be able to tell you a very shameful story where I said something and they understood something else.
So I am sorry SFB and others but grammar is useful, and do serve a purpose.