Yes, according to this morning's readings - according to Jesus - the "undesirables" among us are the ones to whom the Kingdom of God belongs. They are the favorites of the God who Sirach says is "not unduly partial to the weak." Rather God is fittingly partial to them as the Sirach reading itself and the rest of today's liturgy of the word make perfectly clear!
This means that any separation from God's chosen poor amounts to excluding oneself from the Kingdom white Christians spend so much time obsessing about.
So, today's readings are much more radical than usually understood. The parable of the Pharisee and the tax collector - of the pope and the pimp in St. Peter's - is not an affirmation of conventional morality. It's not even a celebration of imagined virtue on the part of the poor or about repentance. It rejects all such ethnocentric hypocrisy! Jesus' parable is not even about approving conventional wisdom concerning pride and humility.
As always with Jesus' teachings, it is about the Kingdom of God, about those who belong and about us who exclude ourselves.