Well, they own the coins so they can melt them and use the metal to make hinges if they want. Personally, I'd like think my coins would be a joy to collectors centuries from now, but they won't be without proper care. Many ancient coins we have now are in nice condition because they were put in sealed pots and buried. This was done because there either were no banks or the banks couldn't be trusted. The owners forgot the location of their stash, died, or moved in a hurry, which is why they survived to be discovered more recently. The coins that weren't squirreled away eventually wore down. After a while they ceased to have face value because they didn't have a face. So, they were melted and made into weapons, tableware, new coins, etc. I doubt any ancient coins we have today are here because they survived two millennia of jangling in pockets, pouches, hands of collectors, etc. Cal
Well sometimes with ancients you do. They can have internal crack and over time the metal can develop crystal fractures and rough handling can cause them to break.
Ever see the videos from PCGS/NGC showing how they grade coins? The graders handle the coins with their bare hands.