I think this was a one off and it was just the battery's time to go.
But also consider that when the Ready Brake activates and pulls on the brake pedal, even with the engine off and such, the toad brakes lights will be active. Normally this would not be a problem considering the short time the lights are powered. Get caught up in heavy stop and go traffic along with a marginal but functioning battery could be just enough to send it over the edge.
I'm pulling around an 05 CRV (No Nav) with a Ready Brake. The CRV comes along on any outing that isn't just a weekend trip. Battery hasn't been a problem, yet. Key to unlock the steering and the radio off is all I do.