... Which might be ok if you only use it in the bedroom but not great if it lets you down on stage with no warning. A battery status light wolud seem to be appropriate
Batteries are cheap enough - as a rule I replace mine twice a year and don't worry about it.
One thing to keep in mind is the battery is only being used when a guitar cable is plugged into the guitar. For all kinds of reasons (battery life included), its a great idea to unplug the guitar when you are not playing it