Have you checked this?
Out for a day of shopping? Now you can see if a local store accepts Apple Pay right in the Maps app. Just choose a location and look for the Apple Pay mark. Or look for the Apple Pay mark or contactless symbol at the checkout counter.
Of course if the maps covers Poland too.
Apple Pay is compatible with any NFC reader on the market, so in Poland you should pay virtually anywhere (more than 65% terminals in Poland accept contactless payments - data from 2014)
That's my theory - I don't have possibility to check that.
Here's probably a chart on which American cards are compatible with Apple Pay. As far I know Polish banks are still testing this service so the cards issued in Poland are not accepted.