alright I'll tackle this in bullet point form because otherwise I'll probably just end up rambling.
1. priceless pieces of history. I do not understand the historical value placed on firearms. the way I see it a rifle is a tool. it was a tool used by soldiers to win a war. a trench shovel has just as much historical value as a K98 Mauser, it was used in battle, under fire and saved many a troop from death. I would not get bent out of shape if someone hacked up a milsurp folding shovel and I do not get bent out of shape when I see someone with a hacked up enfield. it's their property and they can do as they see fit with it, I have no place to judge or criticize them for what they do with their own stuff.
2. what does sporterizing accomplish? by cutting down the forward portion of the wood and removing the handguard you remove a great deal of weight, on some rifles this can be as much as 2 and a half pounds of weight that you remove. most hunters are not fit, combat hardened soldiers that are used to carrying a 10 pound rifle everywhere, every pound you can take off means less weight that you are packing across creeks, over mountains and hillsides and in general just less exertion on yourself. why is it so necessary to get the base rifle as light as possible? because once you drill and tap the receiver and put a scope on it for long range shooting you are slapping that weight right back on. not everyone can use iron sights very well and a magnifying scope not only helps increase precision but also aids in identifying game at the last minute and can help prevent firing on the wrong species(IE mistaking a white tailed deer for a mule deer or mistaking a Blonde black bear for a grizzly). yesterday I took my Arisaka type 44 carbine to the range to test out some hunting loads, I rang an oxygen tank at 400 yards on my first try and my little brother nailed it a couple times too but I started a conversation with another fellow that had been doing pretty good with his hunting rifle and I let him shoot mine, he missed a 200 yard oxygen tank by about 2 feet to the left... some people just aren't good with irons...
3. why sporterize? because for one, back in the 50s, 60s and 70s these rifles were dirt cheap when enfields, german mausers, 1917s, and 1903 springfields were $20 at the local sears there was no reason no to, nobody ever imagined that these rifles would one day jump over $1000 in good condition. millions were hacked up and the number of collectable rifles dwindled until now they are so scarce that it's hard to imagine anyone doing that just because of resale value. however when I look at a SKS where there are about 11 million worldwide or a mosin nagant where there were over 18 million I see no reason why not? it's a dirt cheap rifle and it gives you a thorough idea of how your gun functions, operates and just a better respect for it.
I have what I am starting to see as a respectable collection including mosin nagants, enfields, an M1 garand, springfield 1903, couple arisakas, an SKS, and a MAS36. the SKS, one of the mosins and one of the enfields are bubba'd and all by me. the mosin is a POS, it was a budget expiriment that failed miserably. the enfield is a work in progress converted to 45ACP. and the SKS is actually becoming one of my favorite rifles despite how poor of condition it was in when I bought it and how low my expectations for it were. I would take my bubba'd SKS over an original condition SKS of similar origins any day of the week and if I didn't take the time to make the modifications then I would never have known just what these rifles are capable of and that can be said for any military surplus rifle.