The better question is, why not buy handmade soap? By buying handmade soap, you are usually buying directly from small business owners who put care and passion into their soaps unlike any big box corporation that just cares about profit margins. The ingredients used in handmade soap tend to be ones that you can pronounce and understand, as well as being specially matched to be nice and smooth on your skin.
You might not know it, but most commercial soap is considered a detergent more than a soap, helped by a little chemical called SLS or sodium lareuth sulfide. I think I spelled that right, at least! 
Most handmade soaps don’t touch the stuff, and instead use plenty of skin loving ingredients that smell great and do wonders for enhancing your skin’s health.
