Putting money in casinos is not really investing, but gambling. And gambling usually involves a total dependence on luck; a real investment would need to offer you some guarantees or realistic possibilities to increase your capital based on your own decisions, but this is not the case with casinos.
There is actually a certain guarantee to get profit in the long run while investing in a dice site with a house edge greater than 0%. While it's true there's a great risk it still has positive EV for the investor.
No, because 1. Most sites has costs. It´s not enough for the site to have edge, it needs to be higher than the costs. 2. The site need trafic to make a profit. 3. How do you make sure it´s not a scam? 4. You didn´t mention the price the investor is paying.
Far from all casino investments has positive EV for the investor.
What costs are you referring to? The sites I am familiar with (BitDice and BetKing) certainly do make investing +EV. The fee taken for upkeep etc. is not greater than 50% of the house edge, which would still make it +EV for investors. Could you point me to one site where the costs would make investing -EV? I am quite sure one doesn't exist unless it's some site nobody has heard about or would even consider investing in.
EDIT:
As an example BitDice takes 20% of the house edge and rest of this goes to the investors. Which means it is +EV.
At BetKing the house takes 0.25% from every bet and after each week 25% will be deducted from invest earnings. So if your investment makes a loss, no additional fees will be taken but if you profit, 25% of that will be taken. Even this doesn't make investing -EV.