> the expected value of an act that happens at an unspecified time in the future is zero

It doesn't have to be an unspecified time. Imagine you make $100K and want to donate $50K of that every year. One might say "well, I will bank that money instead, buy a property for $250K, then donate the rental income forever". You now have a specific time in the future (almost, depending on how property prices fluctuate in the next 5 years).