Zloty, not euro, and Sunday trading rules

Poland uses the złoty; places that list euro prices are charging tourists a premium, and card payments are universal, so withdraw only what you need and decline the ATM's "conversion" offer. Most shops are closed on Sundays except a few trading Sundays a year, though restaurants, bakeries attached to a café, and small franchise shops stay open. Poles are more formal than they seem; a "dzień dobry" when entering a shop is expected.