The happy kaboomer: I think you are misunderstanding?
Indeed any particular firearm is originally made to be able to shoot but MANY firearms would lose so much value if fired that the owners prudently don't shoot them.
I own many such firearms!
And indeed the day may/will come when "I" choose to sell the guns - if the buyer wishes to pay the price "I" am asking for my unfired specimens then he/she can do so.
But I would MUCH rather retain the increased value of my unfired collector guns and realize that increased value when I sell them - I literally have hundreds of guns I shoot and have shot so I am not tempted at all to shoot ANY of my valuable unfired guns.
Hold into the wind
If it's profit you're saving for/counting on. You'd make more in a savings account.