Won't hurt anything since you are not "regulating" the pressure at all. I have never run one on a mech fuel pump engine, not to say that they dont have a place but if you are running a "normal" mech pump, I dont see a real need. Now, if you are running something more exotic and capable of higher pressures (above about 12 psi), you might want to leave it. If you go too high, you can cause issues with the carb flooding.
Lets see what some of the racers say.