Are you sure there isn't a base amount of water usage captured in the minimum charge? 2 toilet flushes a day (1 solid, 1 liquid) and a 3 minute shower gets you to 8 gals/day before you've washed any dishes or clothes.
I mean, if you are able to keep your water use that low, congrats and keep it up. We could all use more people like you. In reality, I'm guessing you are using a bit more than that however.
It's the actual amount on my water bill. And yeah. 2-3 toilet flushes a day. Probably a 3 minute shower. A gallon or two for plants. The biweekly high-efficiency washer. (And I'm sometimes traveling but much less so recently.) The weekly dishwash. Etc. Surprises me too. But that's what the numbers say. Not even trying to be unusually convervationist.
I mean, if you are able to keep your water use that low, congrats and keep it up. We could all use more people like you. In reality, I'm guessing you are using a bit more than that however.