That's your job. It's all very well and good asking people to "Retweet" or spread the word. But that's not the entire leg work. You have to spread the word. You have to put it infront of as many eyes as you could. But you didn't. It was never going to work.
Rash accusations about the merit of Kickstarter isn't the right thing to do. Investors do check up on these things. If your campaign was still running, and you were making ground, these are the type of things they check. They check your twitter, forums posts, all of this. They promote you. They have to make sure you are a proper professional to promote, and most of all, a good representative.
People invest in you, not your ideas.
If you where doing all you could with your campaign, people would have followed. People aren't born with followings. They make them.
Be it we are unable to judge for ourselves, the campaign of your friends that you say was hard done by, I don't think this conversation can go any further. It's just a differ of opinion.
I just hope onlookers don't scan the thread, and see "Kickstarter is a waste of time". This isn't true.
Kickstarter is alot of work. But, if researched, if done properly, if given 100%, it's a brilliant method. I'd encourage people who are going to take it seriously, to do it.