One of the reasons I don't like the tag, 'Determinist', is this very subject. Then notion that God created for the purpose of creating a people for himself isn't a problem for most people. The problem is that when they heard that God pre-determined all things, they jump immediately into the idea of whether it makes sense for the God of Love to create the reprobate for the purpose of their damnation. That is not why he created, but rather, to make a people for himself. The fact that he created the reprobate for their purpose has everything to do with him creating his people for himself —as you showed from Romans 9. The reprobate were created, and damned, to demonstrate God's glory to the objects of his mercy. Without having created those reprobate, those to whom he showed mercy would not know his mercy in the same regard as they will know with the reprobate being part of his creation.
This is not a matter of chance, but, as all things with God, a matter of purpose.