I think everyone knows that there are high wagering requirements for bonuses that you claim with a deposit, but are there also wagering requirements for the bonuses that you get as a weekly or monthly reward for what you've wagered so far? I mean if you are a VIP member and you are given a certain amount of free spins or some money based on your wagers of the month or week, are those bonuses also subject to some requirements?
VIP or Loyalty program are good and they help you to maximize your profits. Still, they don't guarantee your winning, they are just like free multiplier which supports immensely to your win. Although it is not that easy to become a VIP member or be part of a loyalty program as you need to first fulfill certain t&c. One of those terms in general is to be a high wager client. There is nothing wrong with it as they are meant to attract gamblers to wager more and earn incentives.
You are correct that casinos offer bonuses for good reasons, and nothing is truly free in the sense that there are underlying business reasons behind these offers. Casinos use bonuses as a marketing tool to attract new players, retain exising ones, and make them to spend more money on their sites. The bonuses are designed to provide an incentive for players to choose a particular casino over its competitors as well, so that is to be taken into account aswell.