If you backed in Milestone 1 or 2, then only the Milestone 2 Big Kahuna packages included copies of the game. For the current Milestone, any backing of value $35 and up includes at least one copy.
According to an email from @Grummz to the Em-8ER M2 mailing list, this has now changed. Any package from Milestone 2 that was Emberite ($35) or above, now has a copy of the game included as well. This includes an additional copy for the max backers from the same Milestone.