And it would be so simple to solve. Prepare a tailored list. Instead of using it on all available space, fill only 90% of the space with items from the list. Fill remaining 10% with random items that do not belong to that list.
There is this hypothesis that I've seen floating on HN at times, that Netflix does this to hide the fact that their selection is very small. I'm not totally convinced, but a lot of their UI choices feel like good evidence in favour of this hypothesis.