I can see for long-range hunting putting ear plugs in with animals not alarmed or alerted to a hunters presence, and glassing vs audible sounds being the main way the animals are located. I don't know, maybe I'm way off on that. Where I hunt, shots are going to be 350-400 yds tops, and the animals can appear from a close by draw where I can/will hear them first or see them over a saddle further away, or anywhere in between with the animals typically on the move. Not much time (IMO) to pull off the gloves, insert earplugs and get down on the animal to take a shot.
With the animals closer in range, that motion in and of itself could be seen. Then it becomes herd of running elk and not a herd of elk moving easily through the area that allows for a good shot. With the longer range shots, the elk come into view, and the shot windows are not large with openings they pass through and pause briefly being the opportunity for a well-aimed shot. The time to put in the ear plugs could make a difference. Again, maybe I am way off on that. One shot years ago in the field with a braked rifle has me saying "no mas, never again" and I could not have put ear plugs in window of opportunity the shot needed to be taken in.
I'm all "ears" for thoughts on how to overcome what I see as the main issue for hunting with plugs, in the type of setting I hunt in.