I've been followin em on twitter and seems like Bithumb is doing a new event every month. This time they're offering 20k in Bitcash to new users who with a trade volume of over 17k USD. The last was out of my reach, but this event is really making me consider signing up for them.
Somewhat similar, I think. Most of the information I found on Bithumb cash is in Korean, but I did find a page. To my knowledge its used for purchasing bitcoin, etc. or discount coupons for commissions fees.