Good answer. When you don't have an answer (or simply don't want to admit that you're perfectly happy with fraud and breach of contract as long as it serves the Holy Grail of maximum profit) go back and say "My solution for this problem is you shouldn't have gotten into this problem in the first place." This allows you to maintain your lofty moral superiority whilst dodging the question before you.If my sister was the landlord, i would have advised her to serve the eviction notice 2 years ago. $700 would help make the children's orthodentic work.
The renters would have been long gone and there would be no fraud or breach of contract.
In answer to your question, there is more to a society than than squeezing every penny you can out of whatever you've got. And there is more power than just money. The same "socialist" laws that protect tenants in Toronto also largely saved Canada from the Great Recession. The power of money, the power of the law, and the power of government all work back and forth: cooperating, competing, pushing this way and that, swinging the pendula too far, and then swinging them back. Because adults with the brains of a house plant understand that there is no perfect solution, the interests and the background shift constantly, and everybody's out for their own good.
I understand that you're an extreme propertarian, and that Upton Sinclair's The Jungle is your desideratum. But spare us your innocent, outraged questions about "How could we have become so degenerate that any factor other than maximization of profit is allowed in the discussion?" Only your fellow extremists and the staggeringly stupid are buying it.