On HDP-1.x stack, we can install a cluster with Hive+WebHcat service without zookeeper service. HCatalog can store metadata either in HDFS or Zookeeper depending on the value of property templeton.storage.class. We set it to ZooKeeperStorage in stack definition as this is recommended by the HCat component.
Not having zookeeper service with the property templeton.storage.class set to ZooKeeperStorage might be a serious problem.
Note: Ambari 1.2.0 release had zookeeper as a required service for Hive+WebHcat service.