Yes, unfortunately we noticed the same and it's not just this casino, but many others. Basically, there are two ways: There's a one person who writes these reviews on their own and secondly, casinos give players incentives and encourage them to write positive reviews on them. I've personally seen a couple of promo pages on the official casino website that asked player to write "a friendly" review, send a screenshot to the customer support and them they would get around 30 free spins etc.
There's also customer support service that encourages players to write a review while they're on a live chat with them in exchange for bonuses. We currently gave players the option to click into a checkbox in case the review was motivated by the casino and I also designed a new tool that will help to automatically detect different types of unusual behaviour and assign the reviews different values. It's currently waiting in a queue for the development, but I'm quite sure it will help to adjust the user rating in a way that it will reflect more what players really think about the casinos.
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