Tool roll in the third cage would be my option, but you can probably ride all day without seeing another soul if you head up some of the trails in the less populous states, so 3 drink bottles might make perfect sense.
Good point. I'm too used to associating off-road functional bikes with 'guards but the sort of places where you can enjoy dry weather can also be short of cafe stops. (Might even be a good place to keep the bear spray.)
^ This is a nice looking bike, but where are you going to ride - on this bike - where you can't get by with two bottles? Bit unnecessary, innit?