I haven't donated yet, nor do I plan to, as I don't have PayPal, and wouldn't really use the extra PMs anyway. But that's beside the point.

I don't think that people's hesitancy to donate has anything to do with getting something in return. It's not something subconscious either. It's simply that people feel that a donation to a registered charity helping victims of natural disasters/famine is more worthwhile than a donation to an internet site, even if it's a site as fantastic as EoFF. Reward or no reward, a contribution to Oxfam feels worthwhile, and a contribution to EoFF less so. Whether the recepient is 'selling' something or not isn't a factor.