Arduino I2C level conversion
If you use the i2c pins of the arduino only to pull the signal to ground and to go Hi-Z and leave the bus pull-up for 3.3v it should work, because the logic levels are usually reasonably compatible.

People might use logic converters out of habit - if a chip takes 3.3V and is SPI and you dump arduino's 5V in it's input, you might fry it, but since I2C devices only pull the bus to ground or go Hi-Z, it should be ok.