Apogio raised some interesting questions in the OP with respect to monetization of crypto programs in respect to gambling casinos or the bookies and I think this is a good answer to that. One of the sole reason why your always going to find this and that gambling site in the business of signatures and frankly, I think it’s okay. Not just because I gamble but, it’s just business.
I always assumed casinos have much higher profit margins. Say someone wagers $10k at 2% house edge. That's $200 profit for the casino. Some users wager millions, which means tens of thousands in profit. Trezor may be able to sell 3 different hardware wallets to a very good customer, but that's where it ends. They need many different customers, casinos only need a few highly profitable ones.
Interestingly, there isn’t many places where we get to use Bitcoins and a couple of them Altcoins directly. Most times you do need the services of exchangers to have them in fiat and utilize it to solve a problem but, gambling sites avails you that privilege. They remain one of the few places you could actually utilize cryptocurrencies for a currency. That in itself tells you, they have a place wherever cryptocurrency is mentioned.
I haven’t seen them to have been over done in any case.