Part of this arose from a new mandate via the mayor to crackdown on slumlords or folks with unsecured or abandoned property.  

There are two aspects to the government “crackdown”.

It was a foreclosure and that area was hit hard not only due to the recession but also to the crackdown of illegal immigrants. 

It's only a matter of time before government finds a way to crack down on them and they go away.if you want to make money, get a job and make money through legal, proven means.

A bad area on the other side of town that unexpectedly moved into my neighborhood after federal law enforcement decided it was time for a crack down on gangs, who just relocated to my hood.A bullet through my bedroom window.A drive-by shooting 1 block over that I only woke up to at 4am after hearing a woman screaming outside her house.A friend managing similar properties across town clubbed on the head as he stopped by to collect rent, waking up hours later in the stairwell, pockets emptied. 

Sure, but some states are really starting to crack down on it and in at least a few, it's a felony. 

I am stunned the real estate commissions in various states don't crack down on it. 

I That sums up every experience I have had with them and why states are finally putting legislation in place to crack down on this crap.

Everyone has to do this, including hotels, so it's really not a disadvantage to anyone to have to charge this, although there are some that are "skirting" the tax law there (HI is starting to crack down on these "Illegal" vacation rentals).  

With rental registration/inspections, the city will be able to crack down on illegal rentals.