I've always been wary of actually using the pockets in cargo pants. Too easy to either hurt & break something when you fall, crawl or kneel.
I'm from the courier-bag school, although my bag is designed as a soft briefcase, so it doesn't have the massive flap overtop that courier bags traditionally have. It's also a laptop carrier, and I don't have one, so it balances a bit awkward with an empty pocket in back.
As for the snap-shot problem of not having your camera around, that's one reason to have a phone camera or one of those smaller digicams, the size of an altoids tin. They can't always perform as well as a larger camera, but they can be point-and-shoot and you can carry them anywhere.
Also, by all accounts, the piglet thing is true-- hit some of those rightwing accounts and you'll find some links to the British press.
Re: cellphone cameras...I try not to much of an "image quality snob", but I've never seen a cellphone camera that was above the "toy" category. Not that there's anything wrong with toys...I've had a lot of fun with equally as low-powered cameras. But I guess the thing is, the Canon point and shoots I use can at least take decent wallpaper photos under the right lighting etc conditions, and I can't say that for the cellphone cameras.