The motive of this thread is for us to discuss what will be you stands if online casinos charges you fees on each game you play on them, same way excahges charges you on each trading position you open, and why should excahges charges fees and casinos not charging such fees, First of all the First objective of every business is to generate revenues, so at first I wasn't curious about this, but recently I began to wonder why the difference between excahges and casinos when both have similar features which are licensing and KYC.
If exchanges take trading fee's their call it value added taxes which some part get remitted to the government.
But online cryptocurrency casino's act in the same vain because both trading and Gambling are the same it all aim at either profits or lose, but while gambling plartforms let go of the fees, exchange charges us on each regardless wether we make profits or lose in the trading position.
Strange question. More precisely, you mixed several questions. The obligation to pay taxes lies with you and the casino is not your tax agent (in most countries, maybe there are exceptions somewhere), while the broker can be your tax agent (based on regulations or your choice).
As for the margin that the broker/exchange takes from you, the essence is the same, it is just done in different ways. On the exchange, you are charged a commission in the form of a price spread, in the casino in the form of a house edge. And you are wrong if you think that you do not pay the casino margin if your bet wins.