In my own experience, I don't use my EDC lights heavily. To me, lights that are used heavily, such as for dog walking at night or for your job, are something you grab when you're heading out for that purpose. They aren't on me all the time like a little AAA EDC light. Or else these lights are used at higher power and thus drain very quickly.

Haertig, if you drain the battery of something like a Fenix E01 more than once a year, then you're a real keychain light power user!