At a casino, you are paying ~5% on the dollar and getting some entertainment in return.
With ICOs, in the long run, you might end up paying ~100% on the dollar and getting nothing in return.
The asymmetry between those issuing 'coins' and those buying is considerably greater than the 'average losses' of 5-10% or whatever a gambler might have at a Casino.
Also - a lot of Casinos end up losing money because they have to 'give too much away' to consumers in terms of the experience, food, drinks.
More wealth-per-dollar will be transferred to investors from ICO's than at Casinos.
Which is why Hedge Funds are lining up to back ICOs - and not Casinos - it's a better return for them.
https://en.wikipedia.org/wiki/Shell_game