PC Gone Mad

Can`t we correct people's grammar? is it socially immoral? 
I spent 4 years studying English. I have a degree in English Studies. Don't I have the right to correct the grammatical errors of others? Aren't I entitled to that privilege?
My parents spent good money on me to know where an apostrophe goes. Does that mean nothing in society?



P.S this is a joke. not a good one obviously.