I obviously play different games than you, because I use both sticks almost constantly... especially in games where the right stick controls the camera. I more often than not have my thumbs on the sticks at any time I'm not using the buttons for whatever reason. It's the 'default' position, if you like.

Of course, I haven't had cramp from overgaming since I was about 13-16 years old. I guess I have developed a resistance to it. xD