1) Amazon provide goods that are sold by
other businesses. Those
other businesses then pay tax.
2) Which tax haven are the royalty payments sent to? The Netherlands isn't a tax haven.
3) Royalty payments of Intellectual Property covers a lot more than just Amazon or Google.
4) The centralisation of royalty payments is an obvious simplification by Amazon et al. Why deal with dozens of tax regimes, when you can deal with just one. Just plain common sense.
5) Amazon provide a huge amount of items that are on sale NOWHERE else. Eg
Want an HDMI cable? High street says limited choice and high prices. Apart from anything else, the physical stores can't provide enough space for the range of items available.
6) Where are the costs of providing the Intellectual Property or Servers centres(Google) offset against?
7) They are effectively foreign companies. Just as, a car made by Mercedes in Germany
will not have UK tax applied against it.