ZK – and the reason given is because a Yid won’t regret it if his request is not fulfilled. Meaning he understands that he does not have the ability to force G-d’s hand, and therefore is giving whole-heartedly in any event,
1)while many people donate to these places expecting a yeshuah, as evidenced by those who complain afterwards (including in other YWN CR threads) that it didn’t work for them.
2)and these places barely stop short of promising that it will work for you.