Disadvantage of using low resistor value for pull up (Strong pull up)

I was trying to choose a resistor value for a pull-up resistor I will use in my project. The project will have I2C communication and SMBus communication. When I was searching on the internet, I have seen some sentence that says using low resistor value for a pull-up resistor causes higher energy consumption. Is it the only disadvantage? If the only advantage of using a pull-up resistor is to reduce energy consumption, would the SMBus or I2C communication work without any pull up resistor? And how much energy does it save if I use 2 k pull up resistor, would it reduce consumption drastically? Thanks beforehand.

• "And how much energy does it save if I use 2k pull up resistor ..." Compared to what? Can't you work it out? Power dissipated is given by $P = \frac {V^2}{R}$ while the input is pulled low. Multiply that by the duty cycle % low time and you've got your average power. – Transistor Apr 12 at 8:48