Why do we care about grammar? Not because we're tight-lipped, red-pen-wielding, fun-policing bananaheads (although we totally are). And not because grammar posts give us a lame excuse to post stock photos of male models (well, kind of because of that).
We care about grammar because when people break the rules, confusion results. Just as good manners are about making other people feel comfortable, good grammar is about making readers feel oriented.
And it's annoying to feel disoriented just when you're trying to crush your friend, as this Sparkler