Many people have boundaries when it comes to donating, especially when it comes to time. I no longer donate my time to the local soup kitchen because I got tired of being harassed by homeless drunks. Sure, many of them were sweet but a few of them were inappropriate and downright threatening. I still donate food, but I'm not going back there. A person's reasons for donating (or not) are nobody's business. A lot of organizations have even modified how they accept donations to the specific ways people want to give. Hell, even the AHA changed their CPR guidelines because good Samaritans don't want to perform mouth to mouth (30 immediate chest compressions). If you feel so passionately about this, work with your local organizations to make it easier for people to donate.