1.
I was exploring an old furniture store/maker with a female friend of mine who is not an explorer but wanted me to shower her some stuff, I took her there because the location is already very well known and its pretty blown out.
We're walking through the place and I hear voices coming from the entrance, I told her to hide. She hid in a back room and I walked towards the voices. It was 3 guys with paint and masks. I raised my hand palm out and said "I'm a photographer" they just said "We're painting" I said okay, and I chatted them up a bit and they seemed like alright guys so I went into the room and got the girl out. When they saw her they realized that I had "interviewed" them before letting them know she was with me. I didn't want to get jumped and her get, well..you know.
We watched them work and I took a bunch of pictures, with the same rules as you - No face shots.
Here is a picture from that warehouse, I'll try to find a picture of the guys painting.