He could have, at the least, rewarded those who were kind to him.
Self centered.
I know an individual who has made a practice of befriending elderly widows with the intention worming his way into their wills, and cashing in upon their deaths. And, in addition, he gets whatever he can acquire in the way of sellable antiques along the way. He’s a true scumbag.
Perhaps Mr. Blum found that the people he really cared about, or cared about him, were all gone, and the only ones left were the ones who just wanted his cash.