> And as for "why are not selling this in every retail store?", the answer is the same - because if they were, no one would buy them.
That's purely hypothetical. How could any prove or disprove the assertion?
The general point, though, is that consumer awareness is essential for sales. People won't buy things that they don't know about. As an indie developer myself, I'm painfully aware of this. It doesn't matter how great one's product is if nobody knows about it. Advertising is very expensive, so it requires vast capital outlays in order to get your products into the minds of consumers and onto the shelves of stores. The big established brands have a massive advantage, making it difficult for competitors to break into the market. Apple itself leveraged its existing brand, with Mac and iPod, in order to promote iPhone. And Apple's primary competitor is Google, who also was already an established brand via search and Chrome.
Remember that back in the day, Microsoft almost destroyed the entire desktop OS market. They almost killed Apple too. Only the Department of Justice put some kind of break on it, and Microsoft let Apple live in order to provide antitrust cover. If MS had for example simply withdrawn its apps from Mac—Office, Internet Explorer (remember that Internet Explorer was originally the default web browser on Mac OS X before Safari!)—Apple likely would have died.