I've been shooting and reloading for 30 years I have NEVER found anyone paying more for old ammo or boxes than new loads are worth. So my advice is shoot them and enjoy. If anyone claims otherwise I have DOZENS of old powder tins and ammo boxes for you to buy if you are willing to pay more than new ammo is worth!
You're running with the wrong crowd then! Vintage ammo collectors are a strange breed of duck. I recently sold my collection (accumulation) of vintage shotshells, an even 20 boxes dating from the 1930's to 60's, and made enough to buy two cases of new AA's had I wanted to.
It takes a different breed of duck to actively seek out empty tins/boxes. Devoted cartridge/ammo collectors want full boxes and the nicer condition the more they pay. I suspect the empty ammo box movement gained traction because of shipping regulations and costs.
I used to shoot a lot of skeet, trap, Clays. Like every one else, in the beginning I believed in the Gospel of Heavy Shot Charges and shot 1 1/8oz at everything. Then I wised up and dropped to 1oz loads with commensurate lighter powder charges and found my scores improved, shoulder improved, and saved a bit of money because I was loading my own. (Every Wednesday evening I did "The MEC Shuffle" so I could shoot every weekend.) Toward the end I was playing with 3/4 & 7/8oz loads for 16 yard trap and all skeet - and my scores didn't deteriorate. Granted, I shot O/U's and SxS's so didn't need to force feed an A-5, but comrades of mine were shooting gas guns and moving into the realm of light shot charges too.
