I took my first archery deer out of a natural blind, but this year I took one from an enclosed blind, and I've found that enclosed ground blinds, whether they are permanent or pop-ups have HUGE advantages. It has already been noted that you can get away with more movement, like drawing your bow, without spooking game. But enclosed blinds also allow you to be more comfortable in almost all weather conditions; they protect you from the sun, rain, snow, and wind. With a natural ground blind, you have to pay attention to the wind direction as much as you would with a tree stand, meaning you may have to skip certain blinds on certain days, and a shift in wind direction or a swirling wind can ruin your hunt. But in my enclosed ground blinds, with just a narrow window open in front, I don't even check wind direction anymore, because the deer never seem to wind me.
Some say, if you have to brush in commercial blinds, what's the point? All of the advantages listed above is the point.
Paul