It hard to get the point you are trying to put forward but if you are talking about insufficient betting information in gambling site's then you may be right not all gaming site make public how much was use to place bet but will always published the winning amount. That is wrong and need to change.
The casinos do that in order to entice the players and the gamblers love it too. They lose their money while gambling and now they are sad and frustrated because their inner dream of making money went down.
So they get enraged and become defiant and stubborn to win back everything but not look back at the logic. While most gamblers are mentally not stable at this point, because those who are, they stop gambling; most end up rage betting and losing all.
There is no point in calling the publishing of bet amounts as bad or unethical, its a free market here. Nobody to regulate it.