I agree! We spent 4 days in the Canyon, and although we were loaded down with heavy packs, we had plenty of time to stop and take pictures, play in the creek, and relax. We met quite a few people running rim to rim or hiking rim to rim. You don't have to get a backcountry permit, but the pressure of moving through the Canyon so quickly just doesn't seem fun to me.
Next summer we are going to hit the much less traveled trails and do some serious backcountry hiking. I wish I could just live in the Canyon forever. SO beautiful and so magical.
And the next time after that we're going to do Phantom Ranch so all we have to bring is a change of clothes in a little daypack.
But that being said, I'm still very impressed with people who do a rim-to-rim!!!!