Free tickets for stuff like this is a bit of a tricky situation. Now we have people who have bought tickets directly and thats great, that money goes directly to the lambo purchasing part (they probably already have that much money anyway) however for people who get deposit bonus tickets, people who earned from affiliates and got it, people who wagered and go it, they are all basically getting a ticket for free without spending their money. This is why casino is actually not profiting as much as people think, just calculating how much tickets where bought times the ticket price doesn't make it justice. Are they making ANY profit?
Well maybe, only wetsuit can answer that (maybe thequin as well) but I doubt the number is that high, I would bet on not making any profit so far.
You might be true, their profit might already drop after 1 or 2 months and the deposit to get free ticket bonus come out right away. They might bet themself on BTC price by 31 Dec 2019 and hope for it new high (to pay less in BTC), just watch in the next 1, 2 months especially in the last month if the BTC price drop near 5000 USD mark you might see bigger promotion. i.e: BTC price at prize payout is 5000, they will need to payout 40 BTC which require their monthly cost of 40/6 = 6.67 BTC.