vengeance666 wroteI highly doubt this whole thing is based on actual offer and demand. Exchanges are literally spitting out random numbers to take advantage of the situation under the cover of "offer and demand".
Because the market is small, it is possible that they are doing it.
I have seen very bad practices in these offices:
-Some spreads are reaching 200LL: The guy behind me wanted to buy USD and the exchange office wanted 200LL more than the price he bought mine. Sometimes I think about snatching his customers and offer them my USD because of their rude ripoffs.
-One exchange bought my USD exactly while telling the customer behind me that he is out of USD.