Mardi Gras. New Orleans is full of people who drink too much and behave badly. I’m sure that it’s much nice the rest of the year.
New Orleans has a much more prominent odor than NYC has ever had. It’s not just the tourist district, there’s a pervasive smell of sewage and rot. It merely recedes a little when the weather isn’t hot in wintertime.
I once traveled to NYC for photo shoots several times a year. That black runoff on seemingly all the streets has an odor when it’s wet, like garbage that hasn’t been picked up for too long. It’s more noticeable in the summer with the heat and humidity, not so noticeable when the weather is cooler and drier. From fall color to spring, if there’s a breeze and it’s dry, there’s no particular, generalized odor there, in my experience. That’s saying something, for such a very large city.