For years, the term "donation" referred to payments made by the public for org services — training and processing.

This is covered by the very title of a well-known LRH article:

“So little by little, using donations you give us for your service, your training and your processing, we create little by little areas of sanity."

The Auditor #51, 1970
What Your Donations Buy
(OEC Vol. 2, p. 106)