? Slides -- Design flaw or "the way they all do it"?

Our Jayco requires 12v for the slides, but the battery is not needed as long as we are connected to shore power. When we left for the season last year, I asked my father-in-law if he could keep the battery and keep it charged until the spring. When we arrived here in the spring, we got here late and it was getting dark, so I just connected to shore power and opened up all 4 slides.

It would seem odd that Keystone would wire the slides directly to the battery, but they could have.

-Michael