I think with fixed allocation, people get much higher tokens than that of stake based system in a sense that if say, in a signature campaign of stakes from member to legendary as 1, 2, 10, 20 and 30 respectively, a legendary member that join for just 2 weeks gets much higher total stake than that of a member who even does for 30 weeks. Suppose it were a fixed allocation, one does not care about the higher ranks that join later to make the coin distribution skewed to higher staked ranks.