I think you are right and you raise a very good point.
NBT/USD should be much less profitable for crypto exchanges than other pair NBT/Cryptos.
But still I think it would be nice for an exchange to have NBT/USD since it would enable traders to buy NBT directly.
However if Nu is successful in maintaining the peg, NBT/USD should offer no volatility.
So there is no profit possible like with BTC/USD for example.
This explains why NBT/USD has a very low buy side support on ccedk.
That is why NBT/USD should be offered not to traders (on crypto exchanges) but to consumers (via payment gateways as @mhps suggested here. )
NBT is basically a token you buy for buying things on the Internet. It is a currency.
So overall BTC-E should be more interested in NSR than NBT.