Because I have to remember to take a couple Advil if I want to last a couple-three hours at the helm.
I wrap up my Advil in a piece of aluminum foil and tape it to my cell phone. After I broke my neck my wife freaks out if she doesn't hear from me every couple of hours. So when I stop for gas, etc. I call her and take a couple of Advil... since they are taped to the phone!
Hey, whatever works.
And whatever keeps you moving and riding.