From Kickstarter FAQ:

To be eligible to start a Kickstarter project, you need to satisfy the requirements of Amazon Payments:

  —You are 18 years of age or older.
  —You are a permanent US resident with a Social Security Number (or EIN).
  —You have a US address, US bank account, and US state-issued ID (driver’s license).
  —You have a major US credit or debit card.

So it's a big no-no for a lot of people who happen not to be residents of the US, like me.