The next person that comes along is more than likely not interested in the same gun as the last person... If they were, gun stores would only have to stock a few guns, not dozens...
I'm guessing you don't work in retail? Why would a store be willing to go through these hoops to sell surplus or used guns, but NOT a new gun? In my experience it is the surplus guns they are most hesitant to do this with. YMMV of course.
Next person walking in the store may not want the same item, but the next person wanting that same item probably wont care, skewing my words to fit your narrative doesn't change facts. Inventory on hand doesn't change the effort put into selling stuff, it merely reflects peoples interests in an item, stores can keep a broader catalog with some stock on hand, over just a few items in mass quantities, because this caters to a bigger population, as it adds variety, its that simple. Your local LGS stocking dozens of items is being kind to you by giving you choice, and not forcing you to buy one of 3 options. As in the end it is personal choice and preference. I would know, from the 9 years of retails experience before starting work in my field of study.
Stores are willing to go through the hoops for used or surplus because they are not in new condition, and all have their own marks and scuffs, so the buyer can have a better idea of what they are buying. These rifles also have a commission, that the store takes, for the effort put into selling them. This commission amount is often more in monetary value than what the profitable markup on that same gun new would be (at least to the store)
New guns are new, they haven't left the box since the factory put them in there, the only thing wrong you'll find is a QC or warranty issue, or a personal opinion of it not being good enough. That personal opinion doesn't reflect functionality. There is nothing wrong with a new gun because you don't like it. I have not once seen a wood stock I would have hesitated to purchase on a new rifle. It does depend on what you are buying too, if you're asking pics of a 10/22 or 300$ Turkish shotgun, they store is going to ask you to pound dirt. They may be more likely to do it for a 2k rifle, regardless of the fact that at 2k they are in conditions that don't need inspections.
And yes, I hand picked my Model 70 Super grade maple, so I understand why people do it, I visited when they were not busy, told them I will 100% be buying one and volunteered to pay upfront even before they gave me two boxes to pick from, funny enough I picked the one they had on the shelf for display.
I am not trying to offend anyone here, just trying to give a better perspective why even if an individual thinks that their time is worth something, and they need to be serviced like a princess, sometimes the item in question, the manner of the request, or the mere situation is not worth the stores time to entertain.