The best way to answer this question is to take it to its most extreme example. If you have a hollow sphere, dotted with countless openings, very few people would ever say it has “one hole” even though that follows the same principle as saying a toilet paper roll does. “Holes” count the amount of openings on the surface of an object. It doesn’t matter if the holes connect or not; if it’s two openings on the surface, it’s two holes.