How do winery visits work in Croatia?

Here in Canada, it's common to simply drop into a winery and order a flight of wines in the tasting room. Most Croatian wineries I'm finding online seem to indicate that visits must be booked in advance, and involve a guided tour around the estate along with a tasting + food (and it's fairly expensive, 60+ euros).

Are drop-in visits to wineries not common in Croatia? We want to make sure we plan properly. Thank you!