Considering how many animal charities exist versus non animal charities I'd be interested in the source of that information. I expect, for example, childrens charities are excluded. It sounds more like a figure made up by an organisation that needs donations (Maybe I'm a cynic, but I remember one organisation - name escapes me - doing exactly this in either late 2007 or early 2008).
Plus, I would imagine the fact that most animal charities are doing their best to fix the crap that humans do to animals would influence peoples decisions somewhat.