Just an addendum to your point about overcoming barriers to entry vis a vis webhosting etc: I've seen KS help with material products, too. (I've backed a few). All of them had a physical prototype, whether it was 3D-printed or handmade, but needed to order X thousand units before a professional company would print the game at a reasonable rate, or they needed Y thousands of dollars to order custom tooling for manufacture. And as part of the funding drive, the developers solicited input from an interested audience and tweaked the project before finalizing the design. KS is great for bridging the gap between a developed idea and production.
Yes, the devs could have gone to a bank - maybe - to secure a loan. But it's probably hard to sell such an idea to a loan officer. "See, it's a 4X game but it riffs off a swords and sorcery theme instead of a space opera." Mhm. GTFO, find a different bank.
Kickstarter serves wonderfully as a combination of advertising, market research, and startup money. In one shot the devs can gauge interest, receive input, improve the product, collect preorders, and tap into economies of scale when hiring suppliers or manufacturers.