That is why having more options to deposit in a casino is a good thing in my opinion. Not only they are giving the existing player more option but also there is a possibility of attracting new users from the community of the added cryptocurrency. I also agree that it is annoying for a small time gambler to have his funds eaten by a larger transaction fee when withdrawing. Having the suggested cryptocurrency is a huge savings for us.
The casino must consider lot of factors before adding a new cryptocurrency on their platform.
The security of that blockchain, decentralization or centralization of it, risk to see blockchain rollbacks or attacks, hacks and so on. Adding a new cryptocurrency is not difficult in deployment technically. However, considering about security and potential impacts on the platform, its treasury as well as users is more difficult.
Because after you add a new cryptocurrency, you must have its in treasury, hot wallet to proceed and make payouts for users when they request. Cheaper transaction fee then withdrawal fee are attractive for users but as blockchain users, they must know the basics and risk from altcoin blockchains as well.