This is a straight-to-the-point blog post by David Steven-Jennings describing how to delete RabbitMQ Queues at the Command Line. It culminates in this bash command to delete all queues:
for queue in `rabbitmqadmin -f bash list queues`; do echo $queue `rabbitmqadmin delete queue name=$queue`; done
I made a bash alias called mqdelqs for it. Awesome efficiency!