[int_19h]

It's not "almost always the case". It may be the case for nonprofits that people donate to, but in general there are quite a few 501c4 around, for example, and there are many others: https://en.wikipedia.org/wiki/501(c)_organization#Types

[margalabargala]

The list may be long, but most other categories are extremely narrow. There are very few into which Rebble could fit.