Mystery Battery Draw While Parked UPDATE

Here is what I was told by my local Acura dealer mechanic. We had a new RDX that needed a battery replacement within the first two years. We parked it in our locked garage each night and usually did not lock it up. He said that when just sitting there, many sensors are still functioning like the proximity sensors. He told us to lock it each night, thus turning some of the sensors off, thus protecting the battery. I really don't know if this is true or not but we always lock the car and the truck each time we leave.
People typically drive their vehicles EVERY day, so charging occurs regularly. When you park one that isn't driven much, this really can become an issue. I hardly drive my truck, it sits for long periods of time.