Remember there is a difference between Liquidity Provider Custodians and Sell Side Custodians as defined by the white paper.
LPCs are compensated for allowing greater demand variability in NuBits. If aggregate demand for NuBits is 100 NBT per day, variability might mean some days have 97 NBT of demand, and others have 103 NBT. Shareholders compensate LPCs for providing that 3 NBT in demand variability insurance. In this simplified example, LPCs would ideally be providing 5-6 NBT of insurance in that case so that a spike in demand wouldn’t break the peg. Relevant:
The trading bot should automatically and immediately place these 1,000,000 NBT for sale at a price of 1.002 USD (one USD + a 0.2% transaction fee). If this order fills, then the bot should use the USD proceeds to immediately place a buy order for NBT at 0.998 USD. All funds should be continually on order and the LP custodian’s funds should not be depleted by transaction fees.
Sell side custodians sell new NuBits above LPC prices. Relevant:
Using our formula above, the trading bot would place a sell order for 10,000,000 NBT at a price of 1.0021. The reason it should be 1.0021 instead of 1.002 is that we want dual side sell orders to be executed first, so their funds can be returned to providing buy side liquidity.
The profits from the sale of those NuBits can be used for any purpose shareholders see fit - dividends, share buybacks, or development work.