Hybrids are easily the most unattractive, most unfashionable bikes in existence at the moment. Many of them are very poorly made, they tend to be a bit slow, you can't take them offroad, really, and even the good ones are sort of ugly. If you ride a hybrid, you know that roadies will view you with utter disdain, cool urban fixie-riders will be more polite and pretend you're not there, more because of your attire than because of your bike, and mountain bike riders will blow past you in their SUVs on their way to, well, the mountains. A hybrid rider is clearly at the bottom of the (ill-defined) bicyclists' social hierarchy.
The thing is, hybrids are possbily the most practical car-free invention ever, at least in urban environments. You can put fenders and racks on them, and do no significant damage to their performance. They're not as fast as a road bike, but on pavement anyway, much faster than a mountain bike. If you buy one with a good frame, they're indestructable. You can mange steep hills on them, even if you're old and fat- try that on a fixie. They're a lot cheaper, and a lot lighter, than one of those nice Dutch bikes. Finally- and this is not insignificant- no one will steal it. If you're going to the store, or the pub, in other words, if you're using your bike as urban transportation rather than making a statement or amusing yourself, they're just right.