A person needs money to feed their children and will be broke 3 days before payday. That person can either (a) not get any money at all, or (b) borrow it at a high rate of interest. What, exactly is wrong with option (b)? Don't add extra details like hidden gotchas, loopholes, what happened to a friend of your sister's etc. What is wrong with the situation exactly as I proposed it and why do you find it unethical?
Likewise, if I decide to snap up a property in distress and rent it out, why is there a (as you put it) "serious problem here?" Why is it better to just let the property rot? Again, answer to the facts instead of letting your bias add conditions I haven't specified.
I'm serious: I'm approaching this with an open mind. Tell me why I'm wrong.