To date I hjave earned about $160 back and currently I receive around $1 pr day but there has been some hash upgrades to my plan due to referrals, about 3 or 4 times I received some hash power in total but cannot find out how much this added to my current available plan, so I am confused as to why is this not profitable for many people but it is profitable for me.
This is not profitable to people who had no bonus hash from referrals. If you referred someone and he invested it's like getting commission for making someone put more money into their scam.
You don't remember how much you earned by doing it so we can't do the math, but I don't think their contracts are profitable without all those extras. If you count money some users get for advertising them on the forums or referring people it could be a profitable investment.