I have a battery disconnect switch. It is a blade style on the negative post. When opened there is no flow of electrons as verified by my V meter. I like it, it was cheap, and my batteries maintain charge from all the "ghost" loads the trailer has. (TV, CO2 detector, etc.) And it is much easier and quicker than a wrench and pulling the negative lead. I think John's thinking is correct. But the concerns of the factory about ghost loads and mine are different. When I want the trailer to go to sleep I want it all to go to sleep, even the CO2 monitor. Rodman30 I recommend the cut off. I got mine here:
https://amazon.com/s?k=battery+cutoff+switch+12v