Won't people interpret the restoration of all as a license to sin?
This may be the truth. Even so, the restoration of all things could be dangerous teaching for unstable people who would interpret it as license to sin.
People looking for excuses to sin will always find them under any belief-system. Regarding the salvation of all mankind, Paul said, "These things prescribe and teach" (1 Tim. 4:9-11). Understanding God's true character and plan for His creation lays a healthy foundation for authentic righteousness that comes from whole-hearted trust and love toward the Lord. The greatest commandment of all is that we love Him with all our being. How can we totally trust and love our Creator, and at the same time be totally convinced that His commitment to us is conditional?