Unfortunately these marketplace websites are killing ecommerce and retail in general. They are unregulated, don't require much seller information, and quite often prices are so low because the sellers are not paying the appropriate level of tax/vat. It is the same story with ebay, great for consumers (apart from when it comes to warranty claims), but terrible for the sector.
I know of a seller in my industry that uses (used now thankfully) eBay, Amazon and Play to sell goods, buying them from the distributors through the company, claiming the vat back from the tax man, then selling them privately for a price between the excluding and inclusive vat price; finally writing off the company and moving on. Happens all the time.