It's one of the many things that makes New York so insufferable in the summer—besides the heat, the crowds, the construction, the smells, and the humidity. Being forced to eat or drink outside—with wind, blinding sun, bugs, pedestrians brushing too close, and the way restaurants that have added outside tables often corral their diners in like cows—is simply uncivilized.
I'm not the only one who hates it! New York Times restaurant critic Frank Bruni lamented last fall about "the increased popularity of sidewalk cafes in New York, the number of which has grown by 25 percent over the last four years." He posited, correctly, that people insist on it because it makes them feel like they're in Europe, where sidewalk cafes are more pleasant. (We're not in Europe.)
Even worse, in my experience? The "summer gardens" of bars. Sounds lovely! But the "garden" area is usually just a backyard/storage space they've cleaned up a bit for the simple amusement of us proles, who are pleased so easily. (It also serves as a handy way to shoehorn a few more groups in the bar.) Then everyone crowds in, and the vicious cycle repeats itself.
(I feel sorry for everyone involved in the garden situation—especially the neighbors, who hear the same five versions of the same five drunken conversations night after night, broadcast through their windows in a horrible feedback loop.)
What I resent the most about a city hell-bent on alfresco dining and drinking is the forced cheerfulness it requires. You're supposed to comment on the weather: isn't it great? So great. Lot warmer this week. Oh, it's lovely. If at night: "Look at the stars!" Etc.
The only time this anti-alfresco rule can be broken is if you're dining or drinking on a rooftop. See you at Top of the Tower.