Hah, that's an interesting way to sell a product: "buy this to embarrass people you don't like!". So groups of people who don't like Stephen King' or LeBron James' stances on Twitter could continuously keep their accounts ticked blue, to annoy them...

So, Elon would be providing a way to harass people, I suppose until they think the harassment isn't worth the megaphone-reach that their account has accrued (which is worth less and less the more dickish the CEO becomes).