.
So, logically, the importer pays the VAT, at the rate of the receiving country, prior to removal from customs, for goods imported from outside EU.
Now the importer is out of pocket until the goods are sold on. That incurs some cost, especially when we are talking £000's, even £M's of pounds (sorry Euros). Sometimes, the VAT paid at the country of reception can be higher than the country of sale. Who loses the difference? Is it repaid somehow? How? When?
The answers to these questions obviously bears further costs to the importer/exporter/manufacturer.
To further illustrate the example, suppose Brico Depot (a DIY shed operating in EU) import tools from UK (following a Brexit), they would have to pay VAT prior to removal from customs, but they couldn't reclaim that VAT until goods are sold to the end user, perhaps many months, even years, later.
Whereas goods imported from Spain (i.e. within EU) would be under a Suspensive Arrangement and VAT not collected/paid until sale to end user.
Thus it's obvious that goods imported to the EU, from outside the EU, have a higher cost than goods imported within the EU.