Gotcha. I tried non prime and the 2+ week shipping was a no go. Prime is usually 7-10 day shipping.Prime is free ship on everything amazon sells. Prime is $149 per year. I just put mine on hold - not worth it anymore.
Without Prime its $35 minimum. Same as Walmart.
Difference between walmart / amazon and RA is you can add toilet paper or laundry soap or whatever to your order to make the cut pretty easily, so your buying stuff you would likely buy anyway.
Not sure on Walmart, haven't been there in years.