It's a no go, don't try

Friday night, late September 2018. Security guard in covert pickup truck popped us literally 15 minutes after store closed. Kicked out about 3 others. Was told Burbank has ordinance against staying in cars and police would tell us to leave. Not welcoming for travelers!

Nice Walmart

It's not 24 hours. It closes at midnight. There is a 3 hour customer parking only sign posted. We slept here in our minivan overnight and had no issues. It's also right next to a few big shopping centers.