10% on the net winnings is FAR LESS than the house advantages of 2.7%. The House Advantages is calculated on every bet. You can play long enough, like turn over the bankroll 30x, and it is near sure it is lost.
I have turned over more than 20000 Euro for a net of only 10, such a session should of course be near impossible to win on a wheel with any HA greater than zero.
We must however read the fine print, some games has no HA in some bets but not all. There is a timelimit for a session.
I have never been told to go public with a winning, it is only if you win on special promotions, as they like to show they really pay the winners there. Sometimes they give "free money".´, and the winner is not a fake name.