And the "return" is absolutely different...
I think that these simple things are the sparkle to create the need for separated platforms.
However, many of these alternative croudfunding platforms are not implementing any difference. And there I will support your point of view, there is no need to do that. In fact, it should be better to take advantage of Kickstarter's moment of inertia.
* Specialised support: the croudfunding platform could offer legal and strategic support in the narrow field they are focusing. I think Kickstarter cannot embrace all industries even if they try.
* Specialised tools and rules: Each platform must have extremely distinct interactions with the backers and product outcomes. In an academic platform (as the one being discussed) I'd expect some tools for scientific divulgation (which must be a mandatory "return" from crowdsourced research projects) and collaboration (which must be extraordinarily stimulated). I think Kickstarter will never consider/establish these rules/tools.