This will at least protect you from the fluctuation of the crypto price while you wager.
When someone decide to buy bitcoin or another coin knows that there is a possibility to lose money.He knows the risks.
Its obvious that for the most of the times, the price movement favors you.
Its possible for a player with a winning account to receive the same btc amount as his initial deposit.
Of course that is not a problem if everyone can withdraw all their money the same day.
Bookmaker.eu is trustable and well known bookmaker among gamblers but i dont think ill deposit my btc there just to have dollars