One QR at a Greek periptero shows snack-and-drink prices in the tourist's own language. Locals see the Greek price list. Prices are edited in the panel, not on the wall.
Browser locale and the scan's country route tourists to the price card you published in their language; Greek-speaking customers stay on the local list. Replace a price card from the owner's phone and every scan after that gets the new one.
Free tier includes 1 standard QR code. Upgrade to the paid Eternal tier for blockchain permanence and the recovery key.