Although not a quick read, the go-to analysis of this is "Entrepreneurs Are the New Labor" [^1].

On this theory, the balance of power has shifted to investors, who prefer founders from an institution. And perhaps a certain generation of young adults welcomes this sort of structure more than others might.

Which isn't to say that incubators don't have great value for many people. They do. But they're not the only way to go about starting many businesses, you're correct.

[^1]: http://www.forbes.com/sites/venkateshrao/2012/09/03/entrepre...