Humanity has an ethical obligation to be as environmentally sound as we can. This certainly extends to not using cans and aerosols when we have a product which works just as well, and in some cases better, with almost no environmental impact.
You need not worry about being "as environmentally sound as we can". Nature recycles everything, and extinction is a natural process. Steel can be recycled by humans, or rusted to nothing by nature--your choice. Be sure to leave some trash and junk behind for future archeologists to learn from. I wince at how much information future generations are losing about us as the environmentalists push recycling everything they can get their hands on. We learn about past populations by the trash that is left behind, your rusty Barbasol can could someday be a major breakthrough for future generations to understand how we shaved ourselves.