In Hindu culture, Kubera is the guardian of treasures and he is also the treasurer of Gods. Today, Kuber is widely associated with money, wealth and material possession. Thus we have fake pujas and rituals, fake yantras and fake products sold in the name of Kubera by many individuals and organizations with the promise of making people super rich. Here it is interesting to note that all the Hindu Gods and Goddesses have animals as their vehicle or Vahana. But Kubera rides on a man.
There is only one symbolism of Kuber Riding on Man - how man can be easily made a slave of money, wealth and material possession. It is money that sets your direction; it is often money that decides which path you should take. Finally, a stage comes when it is money that makes all decisions.
This image of kubera riding on man is a wakeup call for human beings to become the master of money not its slave.
It must be noted that modern yantras, images and murtis of Kubera that are sold by individuals and organizations which helps in gaining wealth and protecting wealth never depict Kubera riding on a man. The reason is obvious people will realize the folly of investing in such fake products.
The vehicle of Kubera is known as Nara Vahana. He is a ferocious man with eyes like two-cart-wheels and body as big as mountain. He was born from the leg of Goddess Ambika.