One of the polemical arguments by the PRCA crowd against the doctrine of Common Grace is that, since all things work together for the damnation of the reprobate since they wickedly abuse without thanksgiving the gifts of God in this world, therefore whatever good things given to them will result in their damnation. Therefore, if the ultimate end is damnation, how can we say that whatever God gives is indeed gracious, since damnation is certainly not gracious?
The problem with this argument is that it confuses ultimate ends with penultimate goals. What do I mean by this? Let's take the issue of evil for example. The Bible clearly teaches that God is sovereign over evil. All things work together for the good of those who love God (Rom. 8:28). That means evil in the ultimate scheme of things is "good," in the sense that it results in the good of God's people. But do we therefore say that evil is good simpliciter? NO! Evil is evil. When someone does a wicked deed, that deed is indeed evil. God meant it ultimately for good for the elect, true, but that doesn't diminish its wickedness. So here we see that evil is penultimately evil, even though God intends it ultimately for our good.
Likewise in the issue of common grace, what the orthodox version of the doctrine of common grace (there might be other versions of "common grace" that I think are unbiblical) states is that God's kindness is indeed genuine, in the same way as evil is indeed evil even when God meant it for good. God's kindness is genuine even though ultimately the abuse of God's gifts will result in greater damnation. It is a genuine kindness, in the penultimate this-worldly sense. It is God's universal benevolence from His status as the Creator, and manifests His goodness to all He has made.