That is correct. Switzerland is not a part of the European Union. The manufacturer, Invenda, is located in Switzerland. That is where their headquarters are. It might be possible that their vending machines are produced within the EU (another country where production costs are lower). It might be possible that these specific models (those who offer data collection) are designed for markets outside of EU.
They advertise their product as "Made in EU" (see brochure). This could be made on purpose to implicate that their data collection meets GDPR requirements, leading to believe that everything is compliant with the law.