Again, not sure what you're seeing- there's no adhesive visible at all,and this is while holding them in my hand. Epoxy is really poor adhesive for stones as I've learned the hard way. They're adhered by a very thin layer of 3M spray adhesive. No stones were harmed in the making of my stone porn!
And trust me- the
"other side" isn't wasted. I don't know if you've ever seen a Japanese natural stone, but only one side is ever "dressed". It takes a lot of work to mount or cut one for the EP. You really couldn't sharpen on
that side. It's not normally usable but that depends on the rock.
Of course, for every stone sold for the EP there are probably 300 sold to guys that do straight razors. So it's not like the stones are being "raped" or anything.