I don't know how they'd track it when it's not the same account.

I pledged to the Kikori Kickstarter (which, btw, means I've got some bias in this although I wasn't up for any rewards) so I knew who the guy was, and I happened to notice that he was involved in this one. Even a human reviewer wouldn't have caught that. Well, you could do simple name matching but I don't think that's good enough -- compare this to the no-fly list, for example.

So I'm OK with word of mouth being the governor here. It's also a good indicator that you should research before you pledge. I do a quick web search if I'm backing something from someone I don't know. It helps set my expectations.

Kickstarter campaigns do have to be submitted for approval, so theoretically there is a human reviewer. I'd assume step 1 would be "Google the names of the project founders".

Sure, but then you have the false positive problem that plagues the no-fly list or any other string based name matching system. It'd work for Judah Sher since that's a fairly uncommon name (his Kickstarter is in the top ten results). It wouldn't work for plenty of other people.