Context: it's just one small Carrefour Express in the village of Acarchon. Not all the huge Carrefour supermarkets across France. https://www.ouest-france.fr/nouvelle-aquitaine/arcachon-33120/ce-supermarche-franchise-de-gironde-offre-20-pourcent-de-reduction-aux-clients-qui-paient-en-bitcoin-une-initiative-inedite-39135f82-f152-11f0-831e-0f8a49f41477