A couple years ago I'm driving down to Ocean Isle Beach, NC to take some real estate pictures for a friend of mine. My phone rings. "Hello, this is Billy." A guys voice on the line asks "Do you do wedding photography?" I'm thinking "duh, that's why I'm Billy Beach Wedding Photography". I say "Yep! I'm all about the weddings. When are you getting married?" He replies "Today." I say "what?" He replies "It's a long story, I need a wedding photographer at the Oceanic on Wrightsville Beach in an hour." I say "I can be there". He asks, "How much do you charge?" I reply "$200 per hour." He says, "Perfect, Get here!"
Fortunately I had my kit with me. Camera, lenses, flash, backups...the works. I did a quick u-turn and headed for the Oceanic. I got there within the hour met the groom and got the story. It seems that a friend of the Bride was going to do the pictures. When it got down to the actual day she either got cold feet (it happens, wedding photography is not for everyone) or she showed up and told them she was going to charge them some outrageous amount, I can't remember the full story, possibly a combination of the two. It turned out to be a great wedding. The ceremony was literally 3 minutes long, great people, beautiful bride a great way to spend a Sunday afternoon.
What I've learned from this. Always, always have a camera with you. I routinely have at least a minimalist kit with me. A camera, a couple of lenses, a flash and a backup. (I'll confess my backup for my emergency kit is a point & shoot, although a good point and shoot). I keep my main gear in my office as I don't want to haul it around, but my lightweight kit is always with me.
You never know when your going to get a call to cover an event. Things happen. Someone gets in an accident, gets cold feet or forgot to contact a photographer. Also if I'm driving down the road and see something I think is photo worthy I've got the gear to get a decent shot. Cell phones are great and getting better generation to generation but they still con't replace a dedicated camera.