I am doing the Kafka Quickstart for Kafka 0.9.0.0.
I have zookeeper listening at localhost:2181 because I ran
bin/zookeeper-server-start.sh
In my case, broker.id=1 in server.properties was problem.
This should be broker.id=0 when you use only one kafka server for development.
Don't forget remove all logs and restart zookeper and kafka
/tmp/kafka-logs (defined in server.properties file)[your_kafka_home]/logs