There is also the financial danger of, here I am at Target, may as well get my money's worth for the car gasoline and buy a whole cart full of stuff (from target not amazon). And every dollar I spend at target is a dollar I won't spend at amazon. All because I ran out of laundry detergent.

Every bottle of Tide I buy at target also means amazon just lost out on a toilet paper sale and a paper towel sale and maybe some food if its a supertarget and all that other stuff target sells. Its not amazon selling a $20 bottle of tide but preventing the target sale of a $120 shopping cart full of junk.