hmmm NO. It was not alerted because it was smoking. That became evident post alert.
The initial attention was because it was blocking, or at least interfering with where buses needed to turn. It also was running and had it's flashers going. I hope something like that would draw my attention. The guy I saw interviewed, the street vendor, was a very well spoken, and "clean cut", black guy. Not at all the image that you might have of Times Square street vendor. I was really surprised. He is also a Vietnam veteran, and might just have a bit higher than usual sense of "something not right", developed the hard way.
It was parked at a wack angle.
The hazard lights sometimes indicate “I’ll be right back,” so he might have done that to make sure it was ignored for a while.