Regular World Turnaround Time (100 days) v Economy (70 days)?

If these numbers are correct - How does this happen? I understand regular vouchers come with membership, but would it not make more sense to free up the bottleneck by slowing down the lower tiers to speed up regular?
Successful BST Transactions with: PerryHall, MrSlider, Cent1225, SurfinxHI, Blu62vette, robkool, gowithmygut, coinlieutenant, Downtown1974, MilesWaits, Shrub68, justindan
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