Instead, my answer to the "why is god kind to the reprobate" has been two-fold, "because his mercy will lead to greater condemnation for the reprobate." Piper gave a great prooftext for this at a conference -
4 Or do you presume on the riches of his kindness and forbearance and patience, not knowing that God's kindness is meant to lead you to repentance? 5 But because of your hard and impenitent heart you are storing up wrath for yourself on the day of wrath when God's righteous judgment will be revealed.My second answer was that God preserves and is kind to the reprobate as an act of kindness to His people. This probably could be called "common grace" because it's a grace to His people that has an effect common to all. Today I noticed a text that seems to support that idea -
29 I will not drive them out from before you in one year, lest the land become desolate and the wild beasts multiply against you. 30 Little by little I will drive them out from before you, until you have increased and possess the land.God is speaking to the Israelites and telling them to drive out the ungodly of Canaan. He says that he will go before them and fight for them. Yet, even though His anger burns against the Canaanites, He does not crush them immediately but allows them to live so that the wild beasts would not multiply against Israel, thereby protecting Israel from another danger. This act of grace to Israel turns out to also be a kindness to the Canaanites.