it's a quick introduction/ presentation of all the main features of product. That's how we do it in Italy...it's not a demo.

I can understand it seems a bit weird. Letting people hear the sounds would make far more sense. No one buys an expensive keyboard without hearing it in detail, first.

This kind of video usually has some other longer videos that follows it.

Yeah it would make sense to just get to the longer video without beating around the bush too much.