"How many of you carry them on every hike? If no, why not?"
That's an interesting question. I've seen numerous people on popular trails that carry nothing more than a cheap Fanny Pack and a water bottle, some only an H2o bottle and many nothing at all!
I would love to have a toll booth off sorts (no $$$ involved) in the middle of Snow Lake's trail where people could volunteer their Packs for inspection of contents. I'd wager to say that 80-per cent of all the Dayhikers out there do not carry the Ten Essentials and probably half that number have never heard of them.
With all this $$$ that the U.S. Forest Service collects from that $3.00 B.S. Northwest Forest Pass from the Public, they could make some cheap signs sealed in shatterproof plastic that SHOW the Ten Essentials like a Mini-Mag Flashlight, Rain Jkt or Poncho, 1st Aid Kit, Candle and Bic Lighter, (full) Water Bottle, etc, etc. I saw one of these 'signs' at a Ranger Station near Darrington, WA and thought immmediately what an excellent idea to educate the Public. I'd also wager to bet the 'Ten Essentials-Signs' would help to reduce the number of Search & Rescue calls each year in the lower 48 States to some credible degree. People need education, and REI can't do it all.
Now that Winter is full upon us all. In my smaller Daypack I've got a home-made Candle fired Stove that takes 2-Tealight Candles and has a 20-penny nail that supports a 10-fluid ounce cup above the flame so in an emergency I can melt snow for water and then have a hot ginger tea. I also pack a half dozen chicken boulion cubes and at least 12-tealight candles all carried in a tiny bright red stuff sack.
When I go Snowshoeing soon I'll have my Whisperlite Stove, an 11-ounce gas bottle and 1-liter pot on all Dayhikes for lunch breaks and emergency use in addition to also carrying my Candle fire Stove.
I'm ordering two MEC +15 Winter Evazote Pads that I will cut one in half that'll make 2-pads each about 22" x 37" x 1/2" thick for sit pads on breaks. The second Pad will be used for Winter overnight Backpacking in conjuction with my UL Thermarest Pad.
Other Winter Essentials are insulated Booties, some sort of Bivy Shelter and/or Tarp. Reflective Thermolite Bivy Sacks are great too, one of these combined with a 3/4 length of 3/8" thick Evazote Pad and a VBL would make a great Emergency Overnight Shelter. Throw in a HEAFTY Garbage Sack to put over the foot end of the Thermolite Bivy Sack and you'd be set. Western Mnteering makes a fairly inexpensive integrated 'reflective' Vapor Barrier Liner that could be substituted for a Thermolite Bivy and used instead with a light weight and cheap 6'x8' Tarp from MEC or www.campmor.com