I hope you don't feel like i'm hijacking your thread, but more like suggesting an different viewpoint...
Can you answer the question: "Why don't you just invest in BTC companies and purchase the m/hash you want" This way you pay the same rate but your risk is spread over everybody"
I come from a pure financial background, and "where I'm from" (lol) people price the reduced risk in numbers into the item they're selling. Not happening so much with BTC. Only "smart" reason I can see, is that they are mostly small companies trying to gain popularity by heralding an honest business model along with enticing ROI
I agree that it makes economical sense, but every legit company I've found selling hash power has been too expensive.