Comment by godelski

They take checks by mail. You definitely can do a cashier's check and I'm sure they'd take the "cash in an envelope" method that places like Mullvad do too. Looks like they also support crypto, and that includes Zcash. So I don't think this is a great excuse. The only "can't easily donate" aspect is going to also be tied with the "can't easily get a cashier's check or find an anonymous person to sell me bitcoin for cash" kinda issues, and when you're operating at that level I'm not sure anything is "easy." (but that's not that hard usually)

https://support.signal.org/hc/en-us/articles/360031949872-Do...