When I am not working, I am carrying my camera. I walked into a Target store the other day and decided to bring the D90. After 45 minutes of browsing the isles, I came away with no images. Recently, I happened upon a group of kids on a field trip. I parked the car, pulled out the camera and--without permission--took a few dozen portraits of kids. One teacher finally asked who I was. I handed her my DailyPhotoLA calling card and I told her that I am giving away photos today and told her how to contact me.
For the record, I don't always shoot first and then beg forgiveness--especially with kids. However, I will often give a little nod and hold up my camera, shoot, and say, "Thank you."