How does speculation affect the exchanges?
I guess exchanges earn more money thanks to speculation
More speculation means more trades and thus more trading fees. Apart from that, exchanges can more easily run their dirty tricks, e.g. front-running the orders of their clients and earning even more profits (than they might deserve). If you really wanted to ask about markets (i.e. not exchanges alone) and how speculation affects them, the answer is rather straightforward though twofold. First, speculation necessarily raises prices since in order to sell speculators should first buy coins (i.e. more demand, at least, initially), and, second, speculation contributes to volatility since many more people are willing to buy or sell, and more often than not they act quite in line with each other (herd instinct)