I was on a New York subway going to work one day, about 40 years ago during rush hour. I was surprised to see an empty car and ran to get in it. When the doors closed, I realized why it was empty - a man sat naked from the waist down and there was a heaping pile of poo in front of him. It was the longest trip to the next stop for me. They never took care of the problem, so of course it has grown and grown. I think about how I survived working in New York City, and that was BEFORE Rudy Guiliani took over.
I had quite the same experiences -- plural -- in NYC. Additionally, a colleague of mine "enjoyed" a beating by feral youths at the 66th street station, which contributed to his losing a job he was applying for. Haven't been back in decades now, and passed up the invitation to participate as a speaker in a seminar there. The honorarium was not enough of a lure.