I've been living in New York for a month--too long to still be a tourist, but too short to count myself a citizen--and, while I first sympathized with them, I've come to disdain the tourists as much as anyone. I'm aware that I have no real right to this attitude, but I've come to it honestly from experience, as opposed to presumptuously.
I should also say that I'm using the term "tourist" a bit generally, since I use it to also describe the "bridge and tunnel people" who flood the city during the week and on the weekends. An acquaintance of mine who was born here often remarks that he dislikes these people more than just the standard tourists. They are ersatz New Yorkers, people who drive badly and, when visiting other cities, tend to claim loudly and boldly that they're as New York as it gets. It is inevitable each morning that one of these people almost hits me with their car. My hope is that someday they stop claiming to be from New York and stop saying "the City" whenever talking about Manhatten. There's something so pretentious about it.