lacker the example was just useful to explain how sometimes it can be useful to run randomized algorithms with hash tables. A real world example is a DNS cache

lacker the example was just useful to explain how sometimes it can be useful to run randomized algorithms with hash tables. A real world example is a DNS cache that can't hold more than N elements, you can just remove one at random. Another one is a cache where elements can expire, and you want to perform a lazy cleanup.