My gun show partner Joe specializes in buying it!
He wanders the aisles, constantly looking. He's like the rest of us old retired guys, no budget and refuses to use much common sense. Its why we all have the huge stockpiles of ammo. If pressed, we could double our shooting volume and go for the rest of our lives. But instead we just keep on buying.
I've personally had pretty good luck both buying and selling ammo. Its true there are people who worry. Most experienced shooters can tell a reload from a block away. Don't buy things that scare you. I'm not even afraid of others reloads if they're really cheap. I can always break them down and use the cases and bullets. But it must be really cheap.
There are certain types of ammo I've taken a liking to over the years. When I see them I usually buy them if reasonable. I tend to doubt if the OP here will find one person to buy all his ammo. But it only takes one guy to buy all of a caliber. My experience watching other table partners selling down ammo is they tend to haul it around for a few shows before it finally finds a new home.
One of our friends is a widow. She was selling down his stuff (she had no use for much of it.) The ammo was fun to watch. Some calibers sold the first day it hit the table. Others not so much. One surprise was the 22 mag ammo. She had 15 boxes of it. So after the 3rd show I was wondering if we'd see it again. Well, the next show she brought it back. So I made her a deal. I told her I'd buy all 15 boxes at $5 a box, but she could try to sell it at the show for her $7.50 a box. If she failed, she had a way out and didn't need to lug it around. She sat there brooding and after about a half hour, she took her arm and swept it over in front of me. It had become more of a pain than it was worth.