Well hang on, not necessarily. The donations could be to a sovereign wealth fund of some kind, so long as invested money produces a somewhat reliable income, it

Well hang on, not necessarily. The donations could be to a sovereign wealth fund of some kind, so long as invested money produces a somewhat reliable income, it could be seen as an investment in the eventual utopia UBI fans envision happening once the fund's large enough. Not a terrible way to implement it privately if the state doesn't get around to it now I think of it.