>"There's virtually nothing in stores in New York that you cannot find elsewhere"
This is patently untrue.
Walk down 9th Street between 1st Ave and 2nd Ave where small designers have their own retail shops and ateliers. You can't buy that stuff anywhere else.
Go up to B and H Camera in midtown that has 5 floors of camera equipment and incredibly knowledgeable staff.
Step in to the Gem Spa on 2nd avenue, a news stand in the East Village where the man behind the counters will hand make you an egg cream for a dollar.
Go to the Strand, a book store that has 15 miles of books and some great bargains on new hard cover books.
Walk into the Sunshine Mart where you feel like you've been magically transported into a grocery store in Tokyo.
Visit Old Good Things in Union Square which is basically an architectural salvage store. Many of the pieces are sourced locally.
Venture over to The Market on Mulberry where artists and designers sell their hand-made wares directly.
Step into Lobels Prime Meats on the Upper East Side and tell me its like any other butcher shop.
Visit Rough Trade in Williamsburg that is perhaps one of the best records stores anywhere, specializing in new and special release vinyl.
And the list goes on. There so many of these places. But you won't discover them spending time on Amazon.com. That was point.