If you are a US based customer, new import tariffs apply

The shoes form the following collections: Goodyear welted barefoot shoes, Barefoot Pals and Sneaky Ninjas, are made in the EU.
The general tariff on EU goods coming to the US is 15% levied on the CIF cost (Cost, insurance and freight) (Cost being the price paid by the consumer in this case).

The tariff is charged at the US border only. There is also a merchandise processing fee of USD 6 for shipments under $2,500 in value. There may be a requirement to pay a sales tax which varies by US State and which is paid by the purchaser.
Finally the US Customs do not refund taxes paid if the goods are returned to Gaucho Ninja in EU (or UK).