> EV certificates add green buttons with company names. Registrar checked that this company indeed exists and legal. So you can be sure, that you didn't mistype URL. And may be some users are comfortable with HTTPS scheme.

Yeah, but those are companies that might as well have non-hidden websites, or be serving .onion mirrors of their regular domains.

The main "use case" for .onion domains are people for whom EV certificates would defeat the whole point.