In general, casinos are able to strip any bonus from any player at any time, since the bonus is something you are given for free. The most important part is about players' experience and fairness, I'd say.
Once such a promotion makes you make a deposit because the offer says you should get some reward in return, obviously the casino should honor the offer.
Many casinos send offers worldwide with a tiny note: all terms apply - it is important to read all rules. It is not ideal, but as long as we get used to the fact that every single advert shown on TV is 50% lie - just my opinion though - is this truly so surprising? I believe that honest casinos care to explain clearly, sadly the player should still be on guard 🙁 because casinos reserve the rights. Maybe they feel you have not made enough deposits earlier or you are somehow restricted, well, here comes the experience. The casino should care about your opinion, but possibly it's not worth the bonus...
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