The other day I just did a very heavy rack pull, 635 pounds, which is six plates on each side, and the 25 on each side. The day after, I could feel it in my hips, my back around my butt area, and also my waist. And my upper back, and my biceps.
Why don’t more people do rack pulls? 
First of all, I have never witnessed anyone attempting a one rep max rack pull, that is, attempting to rack pull a very very heavy weight, for just a single repetition, near or at your maximum strength.
One theory I have on why more people do not do rack pulls is that it is not a competitive lift, it is not like a standardized lift which is done at weightlifting competitions. Therefore, powerlifters will probably not be very interested in that, if they compete.
Second, maybe people think that it is not an effective exercise for building muscle, or that it might not be a full body exercise. On the contrary, when I do very very heavy rack pulls, I could feel it in my whole body, just like a deadlift.
Third, perhaps people are afraid of hurting themselves? However I find it to be much more anatomically natural than unnaturally lifting a heavy weight or a barbell all the way on the floor. For myself, being taller at 5 foot 11, doing a deadlift off the floor feels insanely unnatural. I felt much more natural when I did a hex bar/trap bar deadlift with the elevated handles.
Maybe people think it is not difficult enough, and do not attempt it. Yet, assuming you’re not using straps, wrist straps or hand straps, and you are just using a normal grip or mixed grip with chalk, to simply even lift up the weight and have a strong enough grip is quite the challenge.
For example, I have been attempting to rock pool 635 pounds for quite a while now, and have been unsuccessful for about three weeks. After much diligent practice, I finally got it up. Therefore, in the early days my grip strength or my hand strength simply wasn’t enough, or my whole bodily strength wasn’t enough. I recommend you to just try it, put on seven plates on each side, and see if you can simply lift it off the rack.