It is quite useful for 5v master to low power 3v slaves since you just hook the device to power on the 5v side and the slave can get its power from the 3v side.
But as you said in this case it is a 3v master to 5v slave.
However, it is still useful in this application as it removes one wire connection.
The 3v pullups are on the level shifter and get the 3v power from the on device regulator.
Pluses and minus to each design.
--- bill