I really doubt that, I recommend checking Bulgarian supermarkets, one of the poorest EU countries, yet their dairy products cost like double or triple the prices in Czechia, 3.5% milk you can buy here in promo for 0.4EUR, same in BG would cost double or triple in promotion, same with cheese/yogurt, heck even vegetables/fruit are pretty much same as Czechia with much lower purchasing power, Croatia and Slovakia expensive as well, it seems smaller the country, lower the competition, higher the prices, regardless of the salaries