In the first place, no one deserves to be saved, period. This has been alluded to already in this thread, and I’m sure no one will find the point controversial.
In the second place, you have to understand something. If God gives me a whole series of graces to repent, and I consistently throw them out, there comes a point, in justice, where God will simply stop giving me those graces. God has willed that, when that point arrives, He will give graces only because of someone’s intercession. The intercession of the Blessed Virgin is far beyond the intercession of any other member of the Body of Christ, because she is God’s Mother, and she has a special role that she has been given. While it’s true that this special role may strike some folks who have a certain cultural upbringing as being blasphemous, we have to be careful not to commit blasphemy by being scandalized by the role God gave to Mary, too.
Thirdly, the Brown Scapular is not superstitious because, on the simplest level, we are not attributing to an object a power that is proper to God alone. It isn’t the object that saves us, but by being in a state of grace when we die. The scapular is a sacramental, and thus it is used by God to give us actual graces … the graces that we need to fight the good fight. So, when we’re dying, it may well be that wearing a scapular will affect us, through grace, in such a way that we persevere in our faith, and that we are able to properly turn to God and to die in His friendship. But over all: we should be spending our whole lives preparing for our death, complete with forming all the virtues and even the heroic virtues through God’s holy grace. The scapular is one part of that, and it is ultimately a sign of our reliance on the Blessed Virgin, who is the spouse of the Holy Spirit, and through whom God has willed to act in our lives in a special way.