I always keep one in my wallet. Now if I can remember to bring my wallet…
that would go over well... baby in sweltering car, and you’re complaining you lost your wallet... lol
I used to lock them inside back in college quite often. Studying, worrying, running late, etc. so I started carrying a spare and hid one as well. Now I'm out in the woods and places far from help often, so it would be REAL inconvenient to lock them in. Although I can't remember the last time it happened now.