I experience that when a gambling site requires users a 30x rollover requirement for a $5 or $10 bonus. It is funny how they tried to give a promotion but doesn't want users to win it, but we should not be surprised since they are business people and not charity.
Yes, that's business. I think many casino sites will implement a bonus system for their players with certain terms and conditions. But even if they don't want their users to win it, there will still be their players who will win some money and sometimes, those players can win a large amount of money. It is a common thing that has happened in many casinos and they can benefit from losing players. Even though the sign-up bonus is given, the casino still provides the conditions before the players get it and we as players can only comply with it.