Your righteous indignation does not really contribute much. There are billions of people that speak bad English every day. That alone doesn't make their English good. Just saying "a lot of people do it" is not a validation of anything. Every person with native Russian language, at least until they lived in English-speaking country for many years, reliably skips articles and reliably misuses complex tenses, because there's no such thing in their language background. Yet they understand each other perfectly well, moreover - native speakers understand them perfectly well too (maybe they cringe a bit inside, but what could you do?) Does it mean we have Russian American English Vernacular here?

>>> Please explain why Standard American English is superior to AAVE.

I'm not sure what you mean by "superior" here. There's an English language with its grammar rules, and there are common mistakes or detachments from widespread usage patterns which people make in English. What would be the reason some of these should be institutionalized with four-letter acronyms and research programs and, I have no doubt, juicy grants?

>>>> Why do you think SAE is any more valid than AAVE?

Probably the same reason "the" is more valid than "ze". I'd personally prefer the latter, it's easier for me (actually, I'd prefer to get rid of it completely, face it, the whole concept is just a waste of space and time), but stupid English-speaking world insists on using "the". No idea why, maybe you know?