Bastian
I think that is made, to compensate for spending coins. One coin is worth more than 1 Million when using to Change for cash. For a seller to another Player it is not good. For a seller to noone i think it is ok to get less. looks to me that they tried to find an easy system which is quiet fair to all.
I'm almost following this...
However, Bastian's point is legit since we are Managers and there's an economy cycle within the game. As a business owner it's reasonable to expect returns on your investments even when they have served you dividends already.