Albert Barnes Commentary Job 3:15

"Or with princes that had gold, Who filled their houses with silver:" — Job 3:15 (ASV)

Or with princes that had gold - That is, he would have been united with the rich and the great. Is there not here also a slight evidence of the fondness for wealth, which might have been one of the errors of this good man? Would it not seem that such was his estimate of the importance of being esteemed rich, that he would count it an honor to be united with the affluent in death, rather than be subjected to a condition of poverty and want among the living?

Who filled their houses with silver - Rosenmuller supposes that this refers to the custom among the ancients of burying treasures with the dead, and that the word “houses” refers to the tombs or mausoleums which they erected. That such a custom prevailed, there can be no doubt. Josephus informs us that large quantities of treasure were buried in the tomb with David, which afterward was taken out for the supply of an army; and Schultens (in the passage cited) says that the custom prevailed extensively among the Arabs.

The custom of burying valuable objects with the dead was also practiced among the Indigenous peoples of North America, and is still practiced in Africa today. If this is the meaning here, then the idea of Job was, that he would have been in his grave united with those who even there were accompanied with wealth, rather than suffering the loss of all his property as he was among the living.