Hey Russ, sorry to hear this happened to you!! After hearing of this happening to others on this forum, I'm a pump only guy, and even that gets shut off when away or at night. The system still has enough pressure to flush toilet several times during the night, after turning pump off.
Just this past week, while walking my dog at local park, near campgound, I noticed park employees checking on a nice Montana FW, that had water running out the bottom. Yep, owner was gone, white hose hooked up, and I'm guessing water turned on.
Jerry