Okay... you can call it something cool like "Urban Camping" and there are rules like... find a place that is not going to get you shanked or robbed... and just lay your tent out and... have at it world!
But the simple truth is, that people have been urban camping ever since the dawn of cities and travelers. Oh yes, even these lawn gnomes are doing a little bit of urban camping over night.
Look at this guy, does he look like he cares about city ordinances? Well, after coming down from an awesome afternoon trekking around the White Dover cliffs, and hitting the little city of Dover which is wonderful and sweet... there was a parade and Andy Murray went down in flames (what a shock!) and Yes, I did speak with two of the more inept constables in my life. One actually said to me..."Right, leaving town you want to...hang on...oh, you know, I only live around the corner..."