"I have been to the store trying to buy candles or batteries or matches when a hurricane is coming."

Really? I have plenty of matches etc in my home. I think that really is the main presumption: not just urban versus wilderness but how far are you from home. My EDC/PSK mostly has to carry me for a few hours. If I'm caught in a fire or a riot or a terrorist attack, I'm going to be running away, not stopping to make a drink or building a shelter. Water and fire are a concern over longer time periods, 3+ hours. If you want to worry me, you first need a scenario that prevents me getting home.

And second, you need a scenario that prevents me moving onto the next town and checking into a hotel. The UK is quite densely populated. Even if something did take out my home and everything near by (and somehow failed to take out me at the same time), civilisation still isn't far away. Unless you are talking about The End Of The World As We Know It?

I should also say that it's more about emphasis. I do carry fire-making tools, but they are not as important for me as they would be for someone in a wilderness. I don't understand why people think water purification tablets are important. If you can make fire, you can boil water (at least, if you can scavange a tin can to use as a pan - easy in an urban environment). Plus, you can drink dirty water and probably be OK, and even if you're not, it'll be days before the problem matters. Unless you are talking about the breakdown of the national infrastructure including hospitals, which puts us back in EOTWAWKI.

Here, for the record, is my current core EDC:

• Keyring with:
• Keys.
• 2m parachord.
• Proton III LED torch.
• Compass.
• Whistle (modified Fox 40 extreme).
• Serbertool M4 (a very small multitool).
• Safety pins and paper clips (can be bent and cut by M4).
• Spy capsule with 2 tinder and the flint mechanism from a lighter.
  
  Mobile phone (SE P900).
  Handkerchief.
  Vic Rambler (small swiss army knife).
  
  Wallet with:
• Money, credit cards etc.
• Contact info, next of kin, doctor's details.
• Mirror.
• Fresnel lens.
• Waterproof writing paper.
• Fisher Spacepen refill.

That's what I have on me as I sit at home typing this. It's what I cannot leave the house without. As it happens, I also have a small lighter on me, but often it gets forgotten. It's a recent thing for me; I'm still tweaking my EDC (I might try oven bags next - thanks for that tip). I can start a fire with the contents of the spy capsule but I'd have to be desperate. If floods or riots or hurricanes were imminant, I'd carry more.

I'm not going to list my PSK because I don't have separate PSKs for different environments. Suffice it to say that I do carry more stuff when I am travelling more than two miles from home, and then there is more emphasis on fire etc.