For a lot of random things, like... say, a suction cup thingy that mounts my smartphone to a car dashboard, I have no idea which stores are likely to sell such things, and they could have a wide discrepancy in prices. I can type into Amazon and see a list of products and prices, but if I want to buy one at a local retailer I might have to call three or four stores before finding someone who carries the thing I'm looking for. It would be really nice to have a search engine that can search products across brick-and-mortar retailers.
So for another example, I wanted to get a stainless steel pasta strainer. I checked four different kitchen/cooking stores and the ones that had them them only had ones that were too deep, and they were all priced as ridiculously luxurious items, over $90. Then I checked a local hardware store and they had exactly what I wanted and it was only $12. I only thought of that place because I passed it on the way home and was desperate.
Sure, sometimes things take a bit of work and might not be instantaneous or easy. It all boils down to whether or not one values immense convenience over not supporting Amazon.
