1. Pre made professional website templates to choose from
2. Shopping Cart by Google
3. Payment processing options, ie: Paypal etc.
4. Search Engine Optimization (SEO)
You do still have to pay a 2% transaction fee along with the fees assessed by Paypal. So it does end up being more expensive, but, for getting your OWN website it would save a ton of time and effort and it would end up being comparable to what you would be paying otherwise. Shopify also says you don't need your own domain name to sign up but they don't fully explain what your site name would be without one.
I'd love to hear from anyone currently using this site for feedback!