You assume that it's not dangerous even if it doesn't go to folks who would be helped. I disagree: the possibility of contributing to frauds is not harmless. There is also opportunity cost: if you've donated to someone who is incompetent, then you no longer have those resources to fund someone who can make better use of those funds.

Ideally, you want to focus on the folks who can make a difference. Just funding folks with good intentions isn't enough. As an example of a group that appears to want to help drug addicts, but is pretty dangerously incompetent at it, listen to the Prologue and Act One of the This American Life story "Not It": http://www.thisamericanlife.org/radio-archives/episode/554/n...