Why not? According to a random page I found on the internet, kerosene has a coefficient of thermal expansion of 0.00099 per Kelvin. If you can cool it by 50 degrees then you'll be able to store about 5% more fuel in the same volume of tank, which is a nice little upgrade.
r/SpaceX has a lot of good info. Check out the "What are the differences between the Falcon 9 v1.1 and the upgraded Falcon version popularly called the v1.2?" FAQ here: https://www.reddit.com/r/SpaceX/wiki/faq/falcon