I've always paid for 6 retainers, not all of them are full but they are always full on the market board. Keeps a steady large gil stream going. So is there is that aspect if you gave everyone 20 more selling slots, there will be further market place fluctuations versus those who already pay. If you look at the trend these last two patches they have siding more on taking more and more Gil out of the economy.

If you look at item storage objectively they gave the saddlebag and glamour chest free over time. Basically 400 slots just for gear alone. So it wasn't like they didn't add any value to item storage.