Deb of Dhamma Matters wrote an interesting article entitled Weightless Giving, about the practice of Dana, or generosity. She mentions that its meaning is often diluted when Dharma organizations ask for contributions, and call it dana.
It’s interesting in that I’ve encountered very few Buddhist organizations that strictly work on the principle of dana. Most have fixed payments, or give suggestions for “donation” amounts. One exception that I’ve encountered has been Sravasti Abbey in Washington. People can give money for the teachings if they like, and people can choose to give money for the books, shirts and other Buddhist items in the library. They even survive off food that people bring and offer because they don’t buy their own food!
The other place is Maitripa, a Buddhist College in Portland that was established by Yangsi Rinpoche and Lama Zopa Rinpoche. Everything is free, with the exception of the retreats and curriculum courses associated with the college (they do, however, offer generous grants for students).
I think this is actually the best way, though its very difficult for many centers since they survive on these fixed payments. However, being sustained off spontaneous donations gives the donators a chance to really practice generosity, and an opportunity to create merit.