WalMart's official policy created by Sam Walton himself is to allow RVers to park on their lots for up to 3 days. All WalMarts permit overnight camping. However, some cities have created ordinances to ban camping at WalMart. Most of these towns are either RV unfriendly or close to something like a NASCAR track where the walmart would get overrun with campers. There is an ettiquite to camping at walmart. You can find a list of WalMarts and even a downloadable GPS file that contains all the camper-friendly walmarts at the walmart RVing group:
walmartrving | Yahoo! Groups
Safe is a relative question, I have pulled into Walmarts and said no way, drove somewhere else such as a Flying J which usually has RV parking away from the trucks. If it doesn't seem well lit or scary then move on, if not then spend the night and save yourself $30-50 on a campsite.
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2008 Blue Streak Metallic Double Cab 4x4 Limited 5.7L
2009 Outback 310BHS Sydney Edition 10,060lbs 35'10"
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