That sounds like a generalization. There are probably lots of sound businesses that do not have access to traditional capital investment, and would benefit from being on Kickstarter. Additionally, there are businesses that do not clear a bar of "this is a sound business" that have had heaps of traditional capital investment. We are talking about sets with only some overlap.
There are different funding sites with different rules and different popularity due to those rules and the vagaries of advertising and attention. Kickstarter doesn't need to cater to every type of project or business.
The check and balance you're looking for is traditional capital investment, I think?
Because if all things on Kickstarter clear a bar of "this is a sound business", then those projects probably wouldn't need Kickstarter.
edit: for clarity