Hey, maybe my wording was a bit off, I can confirm that we have never paid for any types of reviews, never had and never will. Though I stated Positive ones as I assume no one would pay for negative reviews 
I think that you should ask your staff if that is the case. I very highly doubt that your casino has received all of the positive reviews from 100% legitimate user experience. I am almost certain that some form of incentive has been given to at least some of the people who are writing reviews about DuckDice. That's just my opinion though.
We understand, there might be casinos there that are paying for fake reviews, but sooner or later it might backfired on them, specially if they will go and continue to scam potential users.
As in this case, yeah, no need to have someone paid for reviews, for me casino will gain their reputation naturally. Obviously, if they are really client and costumer centric and gamblers give them positive reviews in this community sooner or later they will get the reputation without incentivizing anyone. Like what the OP it portraying here.