My Subaru, a 2018 outback, would be completely battery dead if I left it parked for more than a week or so. Happened once at the airport, after which I started

My Subaru, a 2018 outback, would be completely battery dead if I left it parked for more than a week or so. Happened once at the airport, after which I started carrying a battery pack car starter. The guy at the airport who have us a jump said it happened all the time with Subarus in long term parking.