Yes. That being said, sugar is used in canning for flavor, preservation, and color. Sweet food generally tastes better, keeps longer, and the color of the food stays bright and fresh. Peaches have enough natural sugar and don't need any sweetener added while canning to be considered safe. But your final product may look a bit different and have a shorter shelf life. Personally, I walk the line between no sugar and low sugar for canning peaches and canning pears.