Those that cannot fill the wagering requirement can just enjoy whatever they have from the bonuses and promotions that they have. But it doesn't end there for most of us, we want to take it out and at least enjoy it with some personal pleasure so someone who's got in, will have to follow the requirement otherwise it's not an important fund for him/her.
That is why I am not too interested to take the bonus because I realize the wagering requirement and others sometime too high for me. I prefer to deposit the minimum amount and start playing as that will not make me confuse to fill the requirement.
But if I think that I can fill the requirement, for example the wagering requirement is not too high, I will take it and see how good my luck. But that will be rare for me to get the promotion as I don't have much allocation money for playing gambling.