I think these things happen far more than we think. As hobbyists pass away, they leave a lifetime's accumulation that may be priceless to them but that prove hard to value and then sell. Their heirs are often grieving, and almost always know very little about the deceased's collections. I knew someone who was a prominent collector in a number of hobbies that aren't as popular any more, including film camera collecting. His widow hired someone to sell much of it for her on eBay. But she had a hard time finding libraries and organizations to accept the books and magazines she wanted to donate. She spent months on that effort, and some of it was futile.