Tabl10, you make an interesting point, which I myself have noted: even most non-native-English speakers have better grammar skills than the average American. Virtually none of the immigrants I know display the same chronic lack of knowledge of basic grammar that is so common among Americans today. They learned their English in different schools in a different culture.
Yes, there are certain grammatical rules that have some leeway or different standards, but there are many others that are simple, have never changed, and are identical in all English-speaking countries. One example would be using an apostrophe in a plural: it's nonsensical, period.
This one really will be my last post here - no 'might' about it.