I would be happy to use Comtesse in the meantime, if you prefer. I would still prefer not to use mine; it feels incredibly pompous to be called a king when I am in no way behaving like one here.
It seems very strange to me as well. I think it has something to do with the inflation of prices, and how much easier it is to carry paper than metal. And no, Alucard is not a financier, however, as a privateer, he is much more practiced learning the ways of new territories and smoothing the ease of any necessary transactions there.