Yes, it's a good thing. Yes, I get annoyed with the people complaining about it. Someone on Facebook was complaining that the money and awareness should all be going to cancer instead since it affects more people.
My friend's father died of Lou Gehrig's Disease 20 years ago. It is good to bring attention and money to this worthy cause.
Why don't people like this challenge? I admit I get tired of hearing about it all the time but as long as everyone is consenting to the challenge and there are no health issues, I see no problem.