I believe you could do like what @/Cobra said above, where people could purchase a raffle ticket for kk in order to win art, or you could do vice versa (like an art competition) where people submit art and you pay kk for it.
I don't think you could do a raffle with just kk, however, as in people purchase a ticket with kk in order to win more kk, as that's pretty much a lottery. You would also likely make kk that way, without really doing anything (ex. raffle is for 50 kk, 20 people enter paying 5kk for a ticket, you end up making 50 kk)
I may be mistaken, though!! @
~Fierce~