First off, I actually like chickens... but I can see why others might not. First of all a lot of us eat chickens and a lot of people don't like to be confronted with the living version of their happy meal... it makes them feel guilty, so instead they just decide to hate the little boogers and the guilt isn't so bad. Second of all chickens carry a lot of diseases, currently the most notable of which are things like bird flu. Also, when kept in industrial settings (either traditional caged egg laying factories or the raising of thousands of heads of meat chickens in one place) they tend to smell... a lot. They also are bad to be around if you suffer from asthma or similiar lung ailments. They are VERY dusty and can actually cause lung problems all by themselves. And of course some people are afraid of chickens, deathly afraid, suffering from a condition known as Alektorphobia, quite literally "fear of chickens." Phobias often don't follow logic, they just are. These and many other reasons are probably why people don't really like them.