because Amazon payments allows you to agree to pay at a later date and cancel that for whatever reason, Paypal etc. do not support this (as far as I know). I al

because Amazon payments allows you to agree to pay at a later date and cancel that for whatever reason, Paypal etc. do not support this (as far as I know). I also assume the reason you can't use the site (as a project creator, anyone can use Kickstarter as a backer) is because of tax issues.