Take any online retail store website. What does it do? It sells products. Sometimes those products have videos and pictures and information about the product. It’s a sales pitch. How is this different to kickstarter? It isn’t. Kickstarter is just another web-based store where you can buy products. The sales pitch has been adjusted a bit to frame the product and the reason for the product so that you look at it from a different angle than you would if you were just buying the 10 millionth vacuum cleaner. The benefits to the customer are presented well, as should be the case for any successful ecommerce site, including rich content and video etc. It is all a sales pitch. The fact that the products dont exist yet or that their existence is dependent upon something YOU do, simply puts some power into your hands. THAT is really the only way that it differs. It’s basically saying that if YOU don’t buy xyz product, then nobody else is going to be able to buy it either. So it put in your hands responsibility for thinking about everyone else, being part of a group/herd, and belonging. That sense of belonging and cooperating and participating to collectively overcome this artificially-made limitation is what you REALLY get from the deal. The product is relatively unimportant. It is a social phenomenon. People power.
Based on that, and on what you said, there is this evil little aspect of the sales world that begins with an M: Marketing. Sales pitches, spinning, marketing, weaving stories, fantasizing, are all forms of the same thing - trying to get someone to invest belief in a product and infuse it with magical powers of value and meaning that it may not otherwise have. Having done so, the person falls in love with their own projected values that they have been convinced/tricked to putting into the product. They then are not really buying into the product, they’re buying into a fantasy! When the fantasy becomes too far removed from the actual physical product - you know, the boring down-to-earth it-just-made-of-matter-and-does-some-things boring materials - then people start to suspect something and label it “over hyped”. Oops - too much fantasy and game is up. But it is this fantasy that people buy. They don’t buy products. Nobody buys products. People only buy dreams, and spinning/weaving/telling the tale of those dreams in such a way as to enthrall a customer and get them involved is simply another form of that exact same method of getting someone to buy into your fiction. That’s why whenever you sell anything you should be thinking not about what the product IS or its functionalities, but on how it benefits the user and furthermore how you can spin a tale about it that paints a picture of it being something totally more awesome than it actually is. Look at most tv commercials and you’ll see this principle in full effect - e.g. chewing gum… supposedly it blows your senses so much that you have to be strapped into a massive warehouse-sized audiovisual megablast in order for you to understand that it’s THAT powerful. You then aren’t buy icky stretchy sticky chewing gum, you’re buying the fantasy. Another example, shampoo - who the heck cares that your shampoo has deep jungle eucalyptus leaf and african cacoba bean extract? It has nothing to do with making your hair any cleaner. The fact is shampoo is just some stinky chemical you put on your head, but that doesn’t sell - what sells is the lavish luxurious fantasy of shower sexiness wrapped in a blanket of effervescent love bubbles.
So in a way you’re right, sell a concept, let people fantasize over it, add in a back-story, tell about how you are struggling and need the money, give some simple early prototypes or concept art, weave a tall tale and paint a picture in people’s imagination of what THEY want to see in it, and then you only need to deal with the dirty business of actually implementing something if they take the bait. It’s a sorry tale but the fact is this is how the world works. We’re all dreamers buying into dreams. And I’m sure a lot of people will feel like somehow this is really evil and sinful to just exploit people like this… because it flies in the face of what so many people do day in and day out - spiritualize this world and try to make it out to be a fantastic place of wholesome goodness - it isn’t, this entire world is a manipulative insane dream and the kickstarter-style practices simply reveal that ugly truth! But that’s another story. 
I also just want to add that this is part of a bigger social trend towards everyone being more creative in general, the whole Web 2.0 people-centric thing where everyone wants to be a published star. It’s the technologicalization of the ego, if that’s a real word. You see this trend in many places including the likes of Unity itself. Unity is lowering the entry barrier for people to make games and content, thus enabling a much larger audience than ever before to make games. It used to be you’d need to be part of a small niche of programmers in order to even consider this possiblity, but now you don’t even need to program. Game development is going casual, just as the casual games movement came about in recent years. It’s appealing to the mass market. It won’t be long before your granny/grandpa will be participating in making games. I think crowd-sourcing is in its infancy, because the people who are developing the kickstarter projects still have too much of their own self tied up in what gets made. The people are starting to be more empowered to have a say in or a hand in their entertainment, as you can see when kickstarter projects offer to include your ideas or let you create a piece of game content. This is just the start! Soon game development will be a SERVICE where you offer to make whatever game the customers want to play, and they get to basically tell you what the game should do and how it should look and what it includes, and then you make it for them … and most likely the making of it will become so automated and AI-driven that you won’t even have to do much work. Total transparency! Then it will really be games made for the people BY the people. How do you like them apples? Imagine someone sitting in their living room talking to the computer like Star Trek members talked to the Holodeck, telling it what scenario to construct, and it simply goes away and generates the game and fills it all in with procedural content and the player totally loves it because it’s exactly what they wanted, and there is no place in that entire picture for game developers. Scary huh - the end really is nigh! (good timing to say that today, I think
