From what you’ve explained, obviously they don’t but, as this isn’t entirely new, it ain’t really popular either, still a good development in the gambling industry and it’s sure to grow to be a norm some day.
We have a few other telegram casino here in the forum but it’s not that popular compared to the normal web based casino we’ve been using.
Some traditional casino have started utilizing telegram mini app and now have an option for their users to make use of telegram (if that’s what they prefer) - in coming years I believe this will gain more traction and some will even prefer it than using website.
Because let us admit the fact that most gamblers are hesitant to play in a telegram-based casino because they can easily disappear without prior warning. So this app won't attract high rollers because the trust factor is kind of low. Unless, for example, stake will launch their telegram app, I believe, they can attract high rollers as it is operated by highly trusted platform.
As you can observe in this forum, most telegram casino don't survive long. They may attract some gamblers at the beginning, but they will slowly fade up until they will shut down their operations.