Bitcoin is used by people in China, Russia, etc to move money without the approval of the government. Americans use it to fund overseas sports books for online gambling. It is used to pay hacking ransoms. I just read that the pot shops in Colorado are using bitcoin ATMs in their offices. The pot shops are not allowed to use credit cards or legitimate banks. Customers can use a Visa to purchase bitcoins on the spot. It is the only method for a "cashless" purchase for pot.
If you are curious, open an account with Coinbase.com. 100% legit company backed by Wall Street. A fun activity to buy bitcoins and then purchase some things with it.