Matt addressed this concern today on the Town Hall and said that we will actually need a proposal to add them to chests. He rethought previous statements, so this is ultimately an invalid proposal. If there's enough support I'll make one to add them to chests. So far this looks 50/50 but will be good to figure out if there's potentially enough support to pass a proposal to add them.
RE: SPS Governance Proposal - Do Not Put Rebellion Packs in Rewards Chests