Fivers aren't suitable for vegetarians, apparently.

[Excited Penguin]

When you say money made of humans, you mean like factory farm people bred specifically to be diced into cash or like recycling predead corpses?

Both could conceivably be problematic, but I was mainly thinking of the former. 

The latter could be okay given prior consent of the person while alive,or by their relatives after death, alternatively. Of course one could think up a society where certain commodities might depend on doing this against people's wishes just as we do with animals in the current one, but we are not even there with animals right now, I don't think, so that point is moot.