I went to a big tech conference in San Francisco a couple of years back. Walking back to the hotel from Moscone Center, I found myself pacing evenly with what

I went to a big tech conference in San Francisco a couple of years back. Walking back to the hotel from Moscone Center, I found myself pacing evenly with what looked to be a bag lady. All of a sudden she loudly yelled "Watch out for that sh*t!" I honestly thought she was having some sort of episode. But then I looked down and saw I'd stepped in it. She tried to warn me.