I know it's a dangerous nit-picky audit trail to start down, but I hate it when I find out that a #charity I donate to spends money on #proprietary software. It makes me want to stop donating, because I know there's a huge amount of money being wasted on something that can and should be $0. Like, without question, $0, if not supportive of #opensource.
(And yes, I know sometimes charitable orgs get $0 proprietary software, but rarely is it $0 across the board.)