It's also to drive direct bookings and not stack with corporate rates. Some agencies still bake in a little bit of a discount so you can book a main cabin ticket, cancel to wallet for the higher value, then use those funds to book when a sale code comes up. Just takes some planning ahead. Would much prefer them to just come back with 20% off gift cards so I'm not anxious sitting on wallet funds that could expire instead of having to do this more risky workaround.