Yes, I always carry a Bic lighter or two. That is what gets used the most often. I would like to hear from people in areas of higher altitude and more extreme cold conditions to see if the lighters work reliably there.

I am 200 feet above sea level and it is bitterly cold (39F!) and my Bic is working reliably. Actually, the higher I go and the colder it gets, the more likely I am to use an iso-butane canister or liquid petro fuel. Recently, I have been impressed with the ability of a LightmyFire knife (essentially a Mora with a ferro rod integrated into the handle) to light my canister.

Darned if I can remember what we lit our stoves with on Denali, but whatever it was, it worked ....

I carry them when hunting and ice-fishing in Minnesota. I always layer my clothes, so I keep a large size Bic in an inner layer shirt pocket to keep it warm. They don't work well when cold. I say the larger size because the little ones are very difficult to light with cold fingers. In an emergency though, you can put a cold Bic in your armpit for 5 or 10 min to warm it up to operating temps.