There are some sites out there that had bitcoin payment integration but no refund policy integrated unlike fiat. This should be looked into by most startup looking into opening an ecommerce platform for people to pay with bitcoin. Among the thing I look at before making any bitcoi payment into any system is the review from other buyers, followed by security and the policies attached to this platforms. Most people don't endeavour to read about a platfrom policy which is something important when dealing with an ecommerce platform.