There is a Facebook group called 'If You Don't Know The Difference Between You're And Your, You Deserve To Die.'
Quite amusing. Although personally, I don't get too wound up about grammar. It's far more important to be saying something interesting than to be saying something correctly.
In fact, I don't believe there even is such a thing as correct and incorrect usage. Not really.
However, I'm making an exception for the new trend towards using initial caps for every word in advertising headlines. This has to stop.