I work for my money, and I pay for people's work. "Donations" is kind of pointless imo. Why donate even to the bitcoin client itself, when you could just charge the communty fees for development? Ever example of donations being useful can be met with an argument for how to earn money through work. Just my opinion.
For the same reason people donate to charities; their purpose isn't earning income by "working" (they already work), it's helping people. Fees are forced; the point of Bitcoin is not having to pay fees to a central authority.