I personally believe this is a balance thing. I used to be the 'business/sales/idea' guy, but taught myself to code.
So to answer your question, yes this person exists. Why did I decide to teach myself to code? I didn't want to have to rely on developers to build and test my ideas.
A business/sales/idea guy can overthink and plan all day. Build requirements docs, plan marketing, research the market, etc etc.
What they can't do is build, release, and see what the response is in the market.
Personally, I think it is a Business Canvas vs. Lean Startup, and I do see these two methodologies in conflict. I've recently witnessed businesses where people spend more time planning than it would have taken to actually build a beta and see what happens.
On the flip side, there are engineers who really don't get the business/sales/ideas side of things. They sometimes need that person to bring the business to them. However, I think it is more rare that an engineer can't find a business.