It is just more "fun" to see the bigger numbers and the bigger increases. You will notice for every car on every forum and at every car meet the numbers people will claim are ALWAYS gonna be Dynojet with STD correction. This gives the highest results, plus it works out since everyone ends up using the same standard for car to car "comparisons".
A local shop was showing my numbers on an SSTT to some local M3 guys, comparing the dyno's and they were amazed at the torque curve
It really makes an M3 look very weak except up near redline where they finally make the HP.