There is plenty of parking lots in Riverdale around that Sam's club. Ive never been kicked out for parking over night at a Sam's club, but some more densely populated areas might tell you to leave.
There is a Walmart next to the Sam's in Riverdale, you can park there for sure.
Parking policies vary from Club to Club because of local zoning restrictions. Click here to locate a Sam's Club and contact information by city and state or ZIP; Members should verify with the Club Manager if it is permissable to use the parking lot for overnight stays.
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