Not to mention, some jobs barely cover living expenses (if they do), and shit happens (cars break, medical expenses etc).
That said I'm a landlord so I see both sides of this. We have had our share of obvious deadbeats (hmm, you want a few extra days to pay the rent--again--while I see you have new rims there on your ride...) and people that break rules. Being a landlord is really hard work and you'd better be prepared to deal with nightmare tenants, including taking them to court. Most are great tenants, but it doesn't take many of the others to make life hell. This is why, I believe, you'll see good places for sale and you think "if this place is making money, why is it for sale?"...it's because people burn out, or were not cut out for it. I'm not, my wife is the tough person

We upgrade our properties with decent stuff--because the less stuff that breaks, that's good for us as we don't have to rush over to fix it.
There's obviously the "slumlord" type landlords out there. For us, it's a retirement investment for the long haul, so if tenants are allowed to perpetually stay for free...we are fucked. And I know for certain that there will be people gaming this. Is it healthy for the economy, or morally right, to put people like us out of business? I'd say no just as it's not good to throw people on the street. This is the type of situation I'd want government to step in and help, but the help has to make sense for all involved.