We talk about the sounds from casino games and how it distracts the gambler's attention from even realizing that they've lost so much already and that's true.. little things like that usually adds up; we're talking about a cool interface and a attractive colour choice, accessibility at ease etc.
As crazy as it sounds, people extend their stay on a casino site for one of such reasons, but i doubt that it can become an uncontrollable feature to look past, especially since you could just put the sound out and stay with the budget.
Other disadvantage also is that gambling with sound turned on will make the device battery to run out faster than they should.
Enhhh, that's out of the topic... Low batteries don't promote irresponsible gambling, or does it?