It's best to keep in mind that your bonding can wear down, too. Acids in the mouth that cause erosion (from acidic foods or from acidic saliva) can dissolve enamel and dental bonding materials too. So, when you use dental bonding to fill erosion craters and divots, it will wear off eventually and need to be re-done.
The value in bonding is that it protects the underlying natural enamel and dentin from further erosion. You're essentially creating a shield for your enamel and dentin, preventing further loss. The shield of bonding material will wear down, but better that than your natural tooth structure.
And, while you can't re-build your lost enamel, you can re-build the worn bondings!