IMHO, It's not really necessary. Sometimes the difference is minimal where the bass freqs are concerned. And if you are playing with a bassist who plays a 5 or 6 string, the top string is usually tuned to low B anyhow, giving you the lower tuning.
I have messed with the tuning on my bass a few times, lowering to A or up to C, and I've D-tuned my 4 string a couple times, just to see what would happen. Usually it only makes the top string a bit too loose.
And FWIW, sometimes tuning the bass down drowns it out in a mix, and live you feel it more than hear it.
YMMV...