The thing with mining is that you can't determine the change in difficulty each round and therefore you can't determine if you'll break-even. You may plug in a 30% increase per month into a calculator and get a result saying that you'll never break-even. It could be that the hash rate increases by only 10% per month and you make a nice profit. Or it could be 50% per month and you make an even bigger loss. So, it's basically gambling on the rate of change of the hash rate.
My view of cloud hashing is that you may as well just play the BDD game on Havelock.
It's true that end users won't know what the difficulty jumps will be. They are forced to hope they make a return. They are taking risk.
The ASIC manufacturers who get hardware for 20 cents to 50 cents on the price they charge don't really have to worry about that since they assuredly will make a profit. All the risk has been transferred to the end user. If life higher risk should yield higher reward. Here we have a scenario where higher risk is yielding lower reward (the end user). If people want to continue that behavior so be it...