Really.
Is it for metal/punk only?
Every demo I enter, they start hammering the bass with a pick.how can you listen to the sound?
Fair question and thread that got highjacked away from the sentiment of your original question. After nearly a decade on 5-string 34" basses, I just bought and am really enjoying two 4-string 30" basses. I only play them finger-style like all my other basses — and play them mostly for traditional jazz.
I think one of the early comments in the thread is insightful: many guitar players would likely feel more at home playing bass on a 30" — and would likely use a pick due to their comfort with a technique that is already natural to them.
Here's a monster on a short scale at the time — Jack Bruce and Cream, finger-style and not punk or metal.