Spotting scope cam

I always see people recording through their rifles, but I wonder, why not get a spotting scope to record through instead? You'd probably have a better image, more stable and better zoom? I'm going to give it a try, in my typical fashion, I'm doing it as inexpensively as I can. My thought process is that you wouldn't have those shaky-cam shots as the trigger is pulled. You'd still get to see everything else, but it would be stable instead of shaking all over the place when you pull the trigger. Obviously not practical for action shots while hunting, but just wondering why no one else has tried this? Here's what I've got:

http://smile.amazon.com/gp/product/B0049IZMUW?psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00


http://smile.amazon.com/gp/product/B000V7AF8E?psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s01


http://smile.amazon.com/gp/product/B00OXKH8D0?psc=1&redirect=true&ref_=oh_aui_detailpage_o06_s01


I might try this too, if it will help. Has anyone tried one of these?
http://smile.amazon.com/gp/product/B00SN3RMW0/ref=s9_simh_gw_p421_d0_i4?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=desktop-1&pf_rd_r=1HB5T99G3YGPACM5PPN4&pf_rd_t=36701&pf_rd_p=2079475242&pf_rd_i=desktop
 
There are several digiscoping adapters available for spotting scopes and binoculars. I've had a couple of them, but the one I like best is the Universal Digiscoping Adapter by Novagrade. They make one for smartphones and also SLR cameras. I've got the one for smartphones. I've been verify pleased with it. Easy on/off, compact and holds the phone steady. I use the iPhone ear buds volume control as a shutter release. The spotting scopes have zero eye relief. I've rigged an adapter to use it on my rifle scope to compensate for the eye relief that works pretty well.